Determining phase tracking reference signals in multiple transmission points

ABSTRACT

A method for a UE in a multiple transmission points communication system, mTRP, scheme, is provided. The method includes receiving downlink control information, DCI, indicating a at least two transmission points scheme for a scheduled data transmission on physical resource blocks, PRBs. The PRBs includes at least a first subsets of PRBs, associated with a first transmission point, and a second subset of PRBs, associated with a second transmission point. The method further includes determining a first PT-RS frequency density for the first set of PRBs based on the number of PRBs in the first set of PRBs and a second PT-RS frequency density based on the number of PRBs in the second set of PRBs. A UE, methods for a base station and a base station are also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.17/106,684 filed on Nov. 30, 2020, which is a continuation of PCTInternational Application No. PCT/SE2020/050988 filed on Oct. 16, 2020,which claims priority to U.S. Provisional Patent Application No.62/932,779 filed on Nov. 8, 2019, the disclosures and content of whichare incorporated by reference herein in their entirety.

TECHNICAL FIELD

The present disclosure relates generally to communications, and moreparticularly to communication methods and related devices and nodessupporting wireless communications.

BACKGROUND

The new generation mobile wireless communication system (5G) or newradio (NR) supports a diverse set of use cases and a diverse set ofdeployment scenarios. NR uses CP-OFDM (Cyclic Prefix OrthogonalFrequency Division Multiplexing) in the downlink (i.e. from a networknode, gNB, eNB, or base station, to a communication device (e.g., userequipment or UE) and both CP-OFDM and DFT-spread OFDM (DFT-S-OFDM) inthe uplink (i.e. from communication device to gNB). In the time domain,NR downlink and uplink physical resources are organized intoequally-sized subframes of 1 ms each. A subframe is further divided intomultiple slots of equal duration.

The slot length depends on subcarrier spacing. For subcarrier spacing ofΔf=15 kHz, there is only one slot per subframe, and each slot consistsof 14 OFDM symbols, irrespectively of the subcarrier spacing.

Typical data scheduling in NR are per slot basis, an example is shown inFIG. 1 where the first two symbols contain physical downlink controlchannel (PDCCH) and the remaining 12 symbols contains physical datachannel (PDCH), either a PDSCH (physical downlink data channel) or PUSCH(physical uplink data channel).

Different subcarrier spacing values are supported in NR. The supportedsubcarrier spacing (SCS) values (also referred to as differentnumerologies) are given by Δf=(15×2{circumflex over ( )}α) kHz whereα∈(0, 1, 2, 4, 8). Δf=15 kHz is the basic subcarrier spacing that isalso used in LTE, the corresponding slot duration is 1 ms. For a givenSCS, the corresponding slot duration is 1/(2{circumflex over ( )}α) ms.

In the frequency domain physical resource definition, a system bandwidthis divided into resource blocks (RBs), each corresponding to 12contiguous subcarriers. The basic NR physical time-frequency resourcegrid is illustrated in FIG. 2 , where only one resource block (RB)within a 14-symbol slot is shown. One OFDM subcarrier during one OFDMsymbol interval forms one resource element (RE).

Downlink transmissions can be dynamically scheduled, i.e., in each slotthe gNB transmits downlink control information (DCI) over PDCCH aboutwhich communication device data is to be transmitted to and which RBsand OFDM symbols in the scheduled downlink slot the data is transmittedon. PDCCH is typically transmitted in the first one or two OFDM symbolsin each slot in NR. The communication device data are carried on PDSCH.A communication device first detects and decodes PDCCH and if thedecoding is successfully, it then decodes the corresponding PDSCH basedon the decoded control information in the PDCCH.

Time Domain Resource Allocation

When the communication device is scheduled to receive PDSCH by a DCI,the Time domain resource assignment (TDRA) field value m of the DCIprovides a row index m+1 to an allocation table. The determination ofthe used resource allocation table is defined in sub-clause 5.1.2.1.1 of3GPP TS 38.214 v15.6.0. When a DCI is detected in a communication devicespecific search space for PDCCH, the PDSCH time domain resourceallocation is according to a radio resource control (RRC) configuredTDRA list by an RRC parameter pdsch-TimeDomainAllocationList provided ina communication device specific PDSCH configuration, pdsch-Config. EachTDRA entry in the TDRA list defines a slot offset K₀ between the PDSCHand the PDCCH scheduling the PDSCH, a start and length indicator SLIV,and the PDSCH mapping type (either Type A or Type B) to be assumed inthe PDSCH reception.

Demodulation Reference Signals (DM-RSs) and Transmission ConfigurationIndicator (TCI) State

Demodulation reference signals (DM-RS) are used for coherentdemodulation of physical layer data channels, PDSCH (DL) and PUSCH (UL),as well as of physical layer downlink control channel PDCCH. The DM-RSis confined to resource blocks carrying the associated physical layerdata channel and is mapped on allocated resource elements (REs) of theOFDM time-frequency grid in NR such that the receiver can efficientlyhandle time/frequency-selective fading radio channels. A PDSCH or PUSCHcan have one or multiple DMRS, each associated with an antenna port.Thus, a DMRS is also referred to a DMRS port.

Several signals can be transmitted from different antenna ports of thesame base station. These signals can have the same large-scaleproperties, for instance in terms of Doppler shift/spread, average delayspread, or average delay, when measured at the receiver. These antennaports are then said to be quasi co-located (QCL). The network can thensignal to the communication device that two antenna ports are QCL. Ifthe communication device knows that two antenna ports are QCL withrespect to a certain parameter (e.g. Doppler spread), the communicationdevice can estimate that parameter based on a reference signaltransmitted to one of the antenna ports and use that estimate whenreceiving another reference signal or physical channel the other antennaport. Typically, the first antenna port is represented by a measurementreference signal such as a channel-state information reference signal(CSI-RS) (known as source RS) and the second antenna port is ademodulation reference signal (DMRS) (known as target RS) for PDSCH orPDCCH reception.

In NR, a QCL relationship between a DMRS port in PDSCH and otherreference signals is described by a TCI state. A communication devicecan be configured through RRC signalling with M TCI states, where M isup to 128 in frequency range 2 (FR2) for the purpose of PDSCH receptionand up to 8 in FR1, depending on communication device capability. EachTCI state contains QCL information.

A communication device can be dynamically signaled one or two TCI statesin the TCI field in a DCI scheduling a PDSCH.

Phase Tracking Reference Signal (PT-RS)

In NR, phase tracking reference signals (PT-RS) have been introduced fordownlink and uplink and multiple different RS densities in time andfrequency are supported.

The PT-RS resource elements are mapped to a single subcarrier in everyK_(PT-RS):th scheduled resource block where K_(PT-RS)=2, 4. So theinverse frequency density is every K_(PT-RS):th scheduled resourceblock. Note that a resource block has 12 subcarriers.

Table 1 shows an example of a table that determines the inversefrequency density to use for PT-RS, depending on the scheduledbandwidth. Hence, if the communication device is scheduled a PDSCHbandwidth N_(PRB) between ptrsthRB1<=N_(PRB)<ptrsthRB2 then PT-RS ispresent in every 2nd RB, i.e. K_(PT-RS)=2.

TABLE 1 Rel. 15 NR inverse frequency density of PT-RS as a function ofscheduled PDSCH bandwidth Scheduled bandwidth Inverse frequency density(K_(PT,RS)) N_(PRB) < ptrsthRB0 PT-RS is not present ptrsthRB0 <=N_(PRB) < ptrsthRB1 present on every 2nd PRB ptrsthRB1 <= N_(PRB)present on every 4th PRB

The network can signal to the communication device using RRC signaling,the scheduling bandwidth thresholds in such table, e.g. ptrsthRBn, n=0,1, per configured bandwidth part to adapt to phase noise characteristicsof the transmitter and receiver.

Furthermore, when PTRS is configured to be present or not by a RRCparameter and if configured to be present, then PTRS can be present inevery 2nd RB by default, unless DL/UL density tables thresholds areexplicitly configured by RRC.

Furthermore, if two thresholds are configured as equal, then theassociated density is not used at all (disabled). For example, in Table1 below, if ptrsthRB0=ptrsthRB1 in the RRC configuration of thresholds,then “present on every 2nd RB” is not used for this communicationdevice. Moreover, if ptrsthRB0=1, then PT-RS may always be present sincethe “PT-RS is not present” field can never be selected as the scheduledbandwidth must be positive. In addition, if ptrsthRB1=273, the maximalscheduling bandwidth (BW) in NR, for the last row of the table, thenthat row cannot be selected, i.e. that density is disabled.

SUMMARY

According to some embodiments of inventive concepts, a method for a UEin a multiple transmission points communication system, mTRP, scheme, isprovided. The method includes receiving a higher layer configuration ofa mTRP scheme. The method further includes receiving downlink controlinformation, DCI, indicating a first and a second TransmissionConfiguration Indicator, TCI, state in one Code Division Multiplexing,CDM, group for a scheduled data transmission on physical resourceblocks, PRBs. The PRBs includes at least a first subset of PRBs,associated with the first TCI state, and a second subset of PRBs,associated with the second TCI state. The method further includesdetermining a first Phase Tracking Reference Signal, PT-RS, frequencydensity for the first subset of PRBs based on the number of PRBs in thefirst subset of PRBs and a second PT-RS frequency density for the secondsubset of PRBs based on the number of PRBs in the second subset of PRBs.

According to some embodiments of inventive concepts, a UE operable in amultiple transmission points communication system, mTRP, scheme, isprovided. The UE includes a transceiver and processing circuitryconfigured to receive a higher layer configuration of a mTRP scheme andto receive downlink control information, DCI, indicating a first and asecond Transmission Configuration Indicator, TCI, state in one CodeDivision Multiplexing, CDM, group for a scheduled data transmission onphysical resource blocks, PRBs. The PRBs includes at least a firstsubset of PRBs, associated with the first TCI state, and a second subsetof PRBs, associated with the second TCI state. The transceiver andprocessing circuitry are further configured to determine a first PhaseTracking Reference Signal, PT-RS, frequency density for the first subsetof PRBs based on the number of PRBs in the first subset of PRBs and asecond PT-RS frequency density for the second subset of PRBs based onthe number of PRBs in the second subset of PRBs.

According to some embodiments of inventive concepts, a method for a basestation in a multiple transmission points communication system, mTRP,scheme, is provided. The method includes transmitting a higher layerconfiguration of a mTRP scheme. The method further includes transmittingdownlink control information, DCI, indicating a first and a secondTransmission Configuration Indicator, TCI, state in one Code DivisionMultiplexing, CDM, group for a scheduled data transmission on physicalresource blocks, PRBs. The PRBs includes at least a first subset ofPRBs, associated with the first TCI state, and a second subset of PRBs,associated with the second TCI state. The PT-RS frequency density forthe first set of PRBs is obtainable based on the number of PRBs in thefirst set of PRBs and a PT-RS frequency density for the second set ofPRBs is obtainable based on the number of PRBs in the second set ofPRBs.

According to some embodiments of inventive concepts, a base station in amultiple transmission points communication system, mTRP, scheme, isprovided. The base station includes a transceiver and processingcircuitry configured to transmit a higher layer configuration of a mTRPscheme and to transmit a downlink control information, DCI, indicating afirst and a second Transmission Configuration Indicator, TCI, state inone Code Division Multiplexing, CDM, group for a scheduled datatransmission on physical resource blocks, PRBs. The PRBs includes atleast a first subset of PRBs, associated with the first TCI state, and asecond subset of PRBs, associated with the second TCI state. The PT-RSfrequency density for the first set of PRBs is obtainable based on thenumber of PRBs in the first set of PRBs and a PT-RS frequency densityfor the second set of PRBs is obtainable based on the number of PRBs inthe second set of PRBs.

Corresponding embodiments of inventive concepts for computer products,and computer programs are also provided.

An advantage provided by the inventive concepts is that the inversefrequency density is correctly determined for multiple transmissionpoints to a communication device leading to enhanced performance whenreceiving PDSCH in the presence of phase noise.

The inventive concepts provide a solution to the problem of determiningan inverse frequency density for FDM schemes 2a and 2b with multipletransmission points since the inverse frequency density depends on thescheduling bandwidth for a single transmission point transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure and are incorporated in and constitute apart of this application, illustrate certain non-limiting embodiments ofinventive concepts. In the drawings:

FIG. 1 is an illustration of a NR time-domain structure with 15 kHzsubcarrier spacing;

FIG. 2 is an illustration of a NR physical resource grid;

FIG. 3 is an illustration of an example of data transmission overmultiple TRPs for increasing reliability according to some embodiments;

FIG. 4 is an illustration of an example of FDM Scheme 2a according tosome embodiments;

FIG. 5 is an illustration of an example of FDM Scheme 2b according tosome embodiments;

FIG. 6 is an illustration of using a single PTRS port for Schemes 2a or2b with PRG size of 2 or 4 RBs according to some embodiments ofinventive concepts;

FIG. 7 is an illustration of using two PTRS ports for Schemes 2a or 2bwith PRG size of 2 or 4 RBs according to some embodiments of inventiveconcepts;

FIG. 8 is an illustration of an example of PTRS RB allocation in Scheme2a with K_(PT-RS)=4 and PRG size of 4 RBs according to some embodimentsof inventive concepts;

FIG. 9 is an illustration of an example of PTRS for scheme 2a with{circumflex over (K)}_(PT-RS)=└K_(PT-RS)/2┘, K_(PT-RS)=4 and PRG size of4 RBs according to some embodiments of inventive concepts;

FIG. 10 is an illustration of an example of PT-RS present every 4th PRBwhen the PRG size is 2 and PDSCH scheduled from two TRPs associated withtwo TCI states according to some embodiments of inventive concepts;

FIG. 11 is an illustration of an example of PT-RS present every 2nd PRBwhen the PRG size is 2 and PDSCH scheduled from two TRPs associated withtwo TCI states according to some embodiments of inventive concepts;

FIG. 12 is a block diagram illustrating a communication device accordingto some embodiments of inventive concepts;

FIG. 13 is a block diagram illustrating a radio access network RAN node(e.g., a base station eNB/gNB) according to some embodiments ofinventive concepts;

FIG. 14 is a block diagram illustrating a core network CN node (e.g., anAMF node, an SMF node, etc.) according to some embodiments of inventiveconcepts;

FIG. 15 is a flow chart illustrating operations of a communicationsdevice according to some embodiments of inventive concepts;

FIG. 16 is a flow chart illustrating operations of a RAN node accordingto some embodiments of inventive concepts;

FIG. 17 is a flow chart illustrating operations of a communicationsdevice according to some embodiments of inventive concepts;

FIG. 18 is a flow chart illustrating operations of a RAN node accordingto some embodiments of inventive concepts;

FIG. 19 illustratively shows different K values suitable for differentslot formats;

FIG. 20 illustratively shows different K values suitable for the sameslot format when different L values are used;

FIG. 21 is a block diagram of a wireless network in accordance with someembodiments;

FIG. 22 is a block diagram of a user equipment in accordance with someembodiments

FIG. 23 is a block diagram of a virtualization environment in accordancewith some embodiments;

FIG. 24 is a block diagram of a telecommunication network connected viaan intermediate network to a host computer in accordance with someembodiments;

FIG. 25 is a block diagram of a host computer communicating via a basestation with a user equipment over a partially wireless connection inaccordance with some embodiments;

FIG. 26 is a block diagram of methods implemented in a communicationsystem including a host computer, a base station and a user equipment inaccordance with some embodiments;

FIG. 27 is a block diagram of methods implemented in a communicationsystem including a host computer, a base station and a user equipment inaccordance with some embodiments;

FIG. 28 is a block diagram of methods implemented in a communicationsystem including a host computer, a base station and a user equipment inaccordance with some embodiments; and

FIG. 29 is a block diagram of methods implemented in a communicationsystem including a host computer, a base station and a user equipment inaccordance with some embodiments.

DETAILED DESCRIPTION

Inventive concepts will now be described more fully hereinafter withreference to the accompanying drawings, in which examples of embodimentsof inventive concepts are shown. Inventive concepts may, however, beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein. Rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of present inventive concepts to those skilled inthe art. It should also be noted that these embodiments are not mutuallyexclusive. Components from one embodiment may be tacitly assumed to bepresent/used in another embodiment.

The following description presents various embodiments of the disclosedsubject matter. These embodiments are presented as teaching examples andare not to be construed as limiting the scope of the disclosed subjectmatter. For example, certain details of the described embodiments may bemodified, omitted, or expanded upon without departing from the scope ofthe described subject matter.

FIG. 12 is a block diagram illustrating elements of a communicationdevice 1200 (also referred to as a mobile terminal, a mobilecommunication terminal, a wireless communication device, a wirelessterminal, mobile device, a wireless communication terminal, userequipment, UE, a user equipment node/terminal/device, etc.) configuredto provide wireless communication according to embodiments of inventiveconcepts. (Communication device 1200 may be provided, for example, asdiscussed below with respect to wireless device 4110 of FIG. 21 .) Asshown, the communication device may include an antenna 1207 (e.g.,corresponding to antenna 4111 of FIG. 21 ), and transceiver circuitry1201 (also referred to as a transceiver, e.g., corresponding tointerface 4114 of FIG. 21 ) including a transmitter and a receiverconfigured to provide uplink and downlink radio communications with abase station(s) (e.g., corresponding to network node 4160 of FIG. 21 ,also referred to as a RAN node) of a radio access network. Thecommunication device 1200 may also include processing circuitry 1203(also referred to as a processor, e.g., corresponding to processingcircuitry 4120 of FIG. 21 ) coupled to the transceiver circuitry, andmemory circuitry 1205 (also referred to as memory, e.g., correspondingto device readable medium 4130 of FIG. 21 ) coupled to the processingcircuitry. The memory circuitry 1205 may include computer readableprogram code that when executed by the processing circuitry 1203 causesthe processing circuitry to perform operations according to embodimentsdisclosed herein. According to other embodiments, processing circuitry1203 may be defined to include memory so that separate memory circuitryis not required. The communication device 1200 may also include aninterface (such as a user interface) coupled with processing circuitry1203, and/or wireless device UE may be incorporated in a vehicle.

As discussed herein, operations of communication device 1200 may beperformed by processing circuitry 1203 and/or transceiver circuitry1201. For example, processing circuitry 1203 may control transceivercircuitry 1201 to transmit communications through transceiver circuitry1201 over a radio interface to a radio access network node (alsoreferred to as a base station) and/or to receive communications throughtransceiver circuitry 1201 from a RAN node over a radio interface.Moreover, modules may be stored in memory circuitry 1205, and thesemodules may provide instructions so that when instructions of a moduleare executed by processing circuitry 1203, processing circuitry 1203performs respective operations (e.g., operations discussed below withrespect to Example Embodiments relating to communication devices).

FIG. 13 is a block diagram illustrating elements of a radio accessnetwork RAN node 1300 (also referred to as a network node, base station,eNodeB/eNB, gNodeB/gNB, etc.) of a Radio Access Network (RAN) configuredto provide cellular communication according to embodiments of inventiveconcepts. (RAN node 1300 may be provided, for example, as discussedbelow with respect to network node 4160 of FIG. 21 .) As shown, the RANnode 1300 may include transceiver circuitry 1301 (also referred to as atransceiver, e.g., corresponding to portions of interface 4190 of FIG.21 ) including a transmitter and a receiver configured to provide uplinkand downlink radio communications with mobile terminals. The RAN nodemay include network interface circuitry 1307 (also referred to as anetwork interface, e.g., corresponding to portions of interface 4190 ofFIG. 21 ) configured to provide communications with other nodes (e.g.,with other base stations) of the RAN and/or core network CN. The networknode 1300 may also include processing circuitry 1303 (also referred toas a processor, e.g., corresponding to processing circuitry 4170)coupled to the transceiver circuitry, and memory circuitry 1305 (alsoreferred to as memory, e.g., corresponding to device readable medium4180 of FIG. 21 ) coupled to the processing circuitry. The memorycircuitry 1305 may include computer readable program code that whenexecuted by the processing circuitry 1303 causes the processingcircuitry to perform operations according to embodiments disclosedherein. According to other embodiments, processing circuitry 1303 may bedefined to include memory so that a separate memory circuitry is notrequired.

As discussed herein, operations of the RAN node 1300 may be performed byprocessing circuitry 103, network interface 1307, and/or transceiver1301. For example, processing circuitry 1303 may control transceiver1301 to transmit downlink communications through transceiver 1301 over aradio interface to one or more communication devices and/or to receiveuplink communications through transceiver 1301 from one or morecommunication devices over a radio interface. Similarly, processingcircuitry 1303 may control network interface 1307 to transmitcommunications through network interface 1307 to one or more othernetwork nodes and/or to receive communications through network interfacefrom one or more other network nodes. Moreover, modules may be stored inmemory 1305, and these modules may provide instructions so that wheninstructions of a module are executed by processing circuitry 1303,processing circuitry 1303 performs respective operations (e.g.,operations discussed below with respect to Example Embodiments relatingto RAN nodes).

According to some other embodiments, a network node may be implementedas a core network CN node 1400 without a transceiver. In suchembodiments, transmission to a communication device may be initiated bythe network node so that transmission to the communication device isprovided through a network node including a transceiver (e.g., through abase station or RAN node). According to embodiments where the networknode is a RAN node including a transceiver, initiating transmission mayinclude transmitting through the transceiver.

FIG. 14 is a block diagram illustrating elements of a core network CNnode (e.g., an SMF node, an AMF node, etc.) of a communication networkconfigured to provide cellular communication according to embodiments ofinventive concepts. As shown, the CN node may include network interfacecircuitry 1407 (also referred to as a network interface) configured toprovide communications with other nodes of the core network and/or theradio access network RAN. The CN node may also include a processingcircuitry 1403 (also referred to as a processor) coupled to the networkinterface circuitry, and memory circuitry 1405 (also referred to asmemory) coupled to the processing circuitry. The memory circuitry 1405may include computer readable program code that when executed by theprocessing circuitry 1403 causes the processing circuitry to performoperations according to embodiments disclosed herein. According to otherembodiments, processing circuitry 1403 may be defined to include memoryso that a separate memory circuitry is not required.

As discussed herein, operations of the CN node may be performed byprocessing circuitry 1403 and/or network interface circuitry 1407. Forexample, processing circuitry 1403 may control network interfacecircuitry 1407 to transmit communications through network interfacecircuitry 1407 to one or more other network nodes and/or to receivecommunications through network interface circuitry from one or moreother network nodes. Moreover, modules may be stored in memory 1405, andthese modules may provide instructions so that when instructions of amodule are executed by processing circuitry 1403, processing circuitry1403 performs respective operations (e.g., operations discussed belowwith respect to Example Embodiments relating to core network nodes).

Reliable data transmission with multiple panels or multiple transmissionpoints (TRPs) has been proposed in 3GPP for Rel-16, in which a datapacket may be transmitted over multiple TRPs (multi-TRP) to achievediversity. An example is shown in FIG. 3 , where the two PDSCHs carrythe same encoded data payload but with the same or different redundancyversions (RVs) so that the UE can do soft combining of the two PDSCHs toachieve more reliable reception. The two PDSCHs can be frequencydivision multiplexed (FDM) in a same slot, or time division multiplexed(TDM) in different slots or mini-slots within a slot.

Different schemes have been identified in 3GPP for PDSCH transmissionsfrom multiple TRPs, including, for example, Scheme 2a and Scheme 2b asdefined below:

-   -   Scheme 2 (FDM): two TCI states within a single slot, with        non-overlapped frequency resource allocation        -   Each non-overlapped frequency resource allocation is            associated with one TCI state.        -   Same single/multiple DMRS port(s) are associated with all            non-overlapped frequency resource allocations.        -   Scheme 2a:            -   Single codeword with one RV is used across full resource                allocation. From UE perspective, the common RB mapping                (codeword to layer mapping as in Rel-15) is applied                across full resource allocation.        -   Scheme 2b:            -   Single codeword with one RV is used for each                non-overlapped frequency resource allocation. The RVs                corresponding to each non-overlapped frequency resource                allocation can be the same or different.

The scheduled bandwidth can be divided into odd and even groups ofadjacent RBs, knows as precoding resource block groups (PRGs). Forexample TRP1 may be using odd PRGs and TRP2 may be using even PRGs (orvice versa). In specification language, TCI state #1/#2 is associatedwith reception in even/odd PRGs respectively. The PRG size can be 2 or 4resource blocks (RB) where a RB consists of 12 subcarriers. Oneexception is that PRG size can also be configured as wideband. When PRGsize is configured as wideband, the first half of the scheduledbandwidth for PDSCH may be assigned to TCI state #1 (i.e. TRP1) andsecond half of the scheduled bandwidth for PDSCH may be assigned to TCIstate #2 (i.e., TRP2).

FIG. 4 illustrates an example of a FDM scheme with a single CW (Scheme2a) in which a PDSCH is scheduled in a bandwidth of 11 PRGs and istransmitted in PRG #1, 3, 5, 7, 9 from TRP1 and PRG #0, 2, 4, 6, 8, 10from TRP2. In this example, the 1st TCI state is associated with TRP2and the 2nd TCI state is associated with TRP1.

FIG. 5 shows the corresponding example of FDM scheme 2b with 2 CWs (2PDSCH) in which PDSCH #1 with CW #1 is transmitted in PRG #1, 3, 5, 7, 9from TRP1 and PDSCH #2 with CW #2 is transmitted in PRG #0, 2, 4, 6, 8,10 from TRP2. In this example, the 1st TCI state is associated with TRP2and the 2nd TCI state is associated with TRP1. Both PDSCH #1 and PDSCH#2 are for a same transport block, TB and may have a same RV ordifferent RVs.

The PT-RS inverse frequency density K_(PT-RS) depends on the schedulingbandwidth for single TRP transmission (as in Rel.15). In previoussystems, a problem is how to determine K_(PT-RS) for the case of FDMScheme 2a and FDM Scheme 2b with multi-TRP.

According to some embodiments of inventive concepts, in scheme 2a and/or2b, the value used for the scheduled bandwidth N_(PRB) when determiningK_(PT-RS) from Table 1 is a function of X, for example ceil(X/2), whereX is the total number of scheduled resource blocks in the scheme 2aand/or 2b resource allocation as indicated by DCI. One advantage is thatthe PT-RS density is correctly assigned also for multi-TRP transmissionsleading to enhanced performance when receiving PDSCH from different TRPsin the presence of phase noise.

In Scheme 2a and 2b, each PRG is utilized for transmission by one of thetwo TRPs only (i.e., each PRG is associated with only one of the two TCIstates indicated in DCI). Also, the DM-RS ports are from one CDM grouponly according to agreement with a comb-based frequency allocationtransmission, divided into odd and even PRGs (except in the case ofwideband PRG, in which case two continuous chunks or RBs are used perTRP). The same DM-RS port number(s) is used in the odd and even PRGs,hence there is no need to configure two PT-RS ports in scheme 2a and 2b.

In Scheme 2a and 2b, in one embodiment, a single PT-RS port is used. Iftwo PT-RS ports have been configured (in case dynamic switching betweenschemes, e.g., between scheme 1a (in which two PT-RS ports are needed)and scheme 2a/2b, is supported), then only the PT-RS port associatedwith the lowest index DM-RS port is transmitted. An example is shown inFIG. 6 , where 11 PRGs are allocated for PDSCH. PTRS port #0 in PRG #1,3, 5, 7, 9 is transmitted from TRP 1 and PTRS port #0 in PRG #0, 2, 4,6, 8, 10 is transmitted from TRP2. In an alternative embodiment, twoPT-RS ports are used but only one of the port is transmitted in anygiven PRG hence even numbered PRGs transmit one PT-RS port while oddnumbered PRG transmit the alternative PT-RS port. The UE thus receiveonly one PT-RS port per RB (or PRG). An example is shown in FIG. 7 wheretwo PTRS ports are used. PTRS port #0 is only transmitted in PRG #1, 3,5, 7, 9 from TRP 1 while PTRS port #1 is only transmitted in PRG #0, 2,4, 6, 8, 10 from TRP2

In scheme 2a, the communication device should not assume that thecommunication device can use the PT-RS transmissions (i.e. the PT-RS inthose subcarriers) from PDSCH PRG associated with different TCI statesin a joint manner, when using PT-RS for tracking the phase. Hence, phasetracking may need to be estimated for each of the two groups of odd andeven PRG separately. (Or the lower and higher set of RB in case ofwideband PRG configuration). The communication device thus performsphase tracking on the PT-RS received in the odd PRG to demodulate thePDSCH (or part of the PDSCH) received in the odd PRGs.

In scheme 2a a single PDSCH is scheduled, but only half of the frequencydomain PT-RS samples in an OFDM symbol containing the PDSCH can be usedfor phase tracking, for the PDSCH received on the same PRGs as the PT-RSassociated with each TCI state, as explained above. An example is shownin FIG. 8 , which is an example of PTRS RB allocation in Scheme 2a withK_(PT-RS)=4 and PRG size of 4 RBs. Here, a total of 6 PRGs are scheduledbut due to the use of two TRPs, only three PRGs are allocated for eachTRP and three samples are available for the PT-RS reception of thetransmission from one TRP.

Thus, the number of PT-RS samples in frequency may be too low for goodperformance. To compensate for this loss, the PT-RS density may beincreased when PDSCH of Scheme 2a is scheduled.

For example, in scheme 2a, the determined K_(PT-RS) from Table 5.1.6.3-2in 3GPP TS 38.214 v15.6.0 may be modified such that the modified PT-RSdensity {circumflex over (K)}_(PT-RS) is used for the scheduled PDSCH.For example, the inverse frequency density may be modified as{circumflex over (K)}_(PT-RS)=└αK_(PT-RS)┘ where α can be ½ or ⅓ astypical values. Another example on how to modify the inverse frequencydensity is {circumflex over (K)}_(PT-RS)=K_(PT-RS)−1. Table 5.1.6.3-2 of3GPP TS 38.214 v15.6.0 is reproduced below where NRB_(O) and NRB₁ arethreshold values as discussed above with respect to Table 1.

3GPP TS38.214 TABLE 5.1.6.3-2: Frequency density of PT-RS as a functionof scheduled bandwidth Scheduled bandwidth Frequency density (K_(PT-RS))N_(RB) < N_(RB0) PT-RS is not present N_(RB0) ≤ N_(RB) < N_(RB1) 2N_(RB1) ≤ N_(RB) 4

An example with {circumflex over (K)}_(PT-RS)=└K_(PT-RS)/2┘ is shown inFIG. 9 for the same PTRS configuration as in FIG. 8 . FIG. 9 illustratesan example of PTRS for scheme 2a with {circumflex over(K)}_(PT-RS)=└K_(PT-RS)/2┘, K_(PT-RS)=4 and PRG size of 4 RBs.

In another embodiment, when scheme 2a is signaled, the scheduledbandwidth, N_(RB), in Table 1 (corresponding to Table 5.1.6.3-2 of 3GPPTS 38.214 v15.6.0, which is reproduced below) for PTRS frequency densityconfiguration is defined as the number of RBs associated with the firstTCI state (or equivalently the second could also be the choice)indicated in a DCI. For the example shown in FIG. 8 , N_(RB)=12 would beused instead of N_(RB)=24.

3GPP TS 38.214 Table 5.1.6.3-2: Frequency density of PT-RS as a functionof scheduled bandwidth Scheduled bandwidth Frequency density (K_(PT-RS))N_(RB) < N_(RB0) PT-RS is not present N_(RB0) ≤ N_(RB) < N_(RB1) 2N_(RB1) ≤ N_(RB) 4

Alternatively, in scheme 2a, the value used for the bandwidth N_(RB)when determining K_(PT-RS) from Table 5.1.6.3-2 in TS 38.214 is thenumber of resource blocks (RB) for the PRGs of the PDSCH which areassociated with one of the TCI states, for example the PRG associatedwith the first of the two TCI states.

For Scheme 2b, the procedure may be simpler, as there are two CWtransmitted, and thus possibly this can be specified so that two PDSCHtransmitted (or alternatively as one PDSCH with two CW that map todifferent RB respectively). A rule can then be based on the following:

In scheme 2b, the PT-RS resource element mapping is established for eachof the two PDSCH independently (i.e. to the scheduled resources of thePDSCH). The communication device should not use PT-RS of one PDSCH asthe PT-RS for the other PDSCH.

Moreover, in scheme 2b, the actual number of RB used for transmissionfrom one TRP, i.e. per PDSCH, is roughly 50% of the total number ofscheduled RB since the resource allocation indicates the total resourcesused for both PDSCH. Hence, to correctly assign the inverse frequencydensity K_(PT-RS) of the PT-RS for each PDSCH, only 50% of the totalscheduled bandwidth should be assumed per PDSCH.

Hence, in scheme 2b, the value used for the bandwidth N_(RB) whendetermining K_(PT-RS) from Table 5.1.6.3-2 in TS 38.214 is a function ofX, for example ceil(X/2) or floor (X/2) where X is the total number ofscheduled resource blocks in the scheme 2b resource allocation, which isindicated in the scheduling DCI.

Alternatively, in scheme 2b, the value used for the bandwidth N_(RB)when determining K_(PT-RS) from Table 5.1.6.3-2 in TS 38.214 is thenumber of resource blocks (RB) for the PDSCH associated with one of theTCI states, for example the PDSCH associated with the first TCI state.

In another embodiment of scheme 2b, the value used for the bandwidthN_(RB) when determining K_(PT-RS) from Table 5.1.6.3-2 in TS 38.214 isthe actual indicated value in the DCI. The determined K_(PT-RS) fromTable 5.1.6.3-2 in TS 38.214 is then modified to the PT-RS density{circumflex over (K)}_(PT-RS) to be used for the scheduled PDSCH. Forexample {circumflex over (K)}_(PT-RS)=[αK_(PT-RS)] where a can be ½ or ⅓as typical values. Another example on how to modify the inversefrequency density is {circumflex over (K)}_(PT-RS)=K_(PT-RS)−1.

Determination of PT-RS Density Taking into Account PRG Size

Using the NR Rel-15 procedure, the inverse frequency density (K_(PT.RS))is determined taking into account the scheduled PDSCH bandwidth, and thetwo thresholds ptrsthRB0 and ptrsthRB1 as per function defined inTable 1. Based on the procedure, it may be determined that the PT-RS ispresent on every 4^(th) PRB. Further consider in this case that the PRGsize is two and PRGs 0 to 11 are used to schedule PDSCH with schemes 2aor 2b. As shown in FIG. 10 , PRGs 0, 2, 4, 6, 8, and 10 are allocated toTRP2 which is associated with the 1^(st) TCI state, and PRGs 1, 3, 5, 7,9, and 11 are allocated to TRP1 which is associated with the 2^(nd) TCIstate. However, following NR Rel-15 procedure with PTRS being determinedto be present in every 4^(th) PRB results in the case that PT-RS is onlytransmitted in RBs corresponding to the 1^(st) TCI state (i.e., RBstransmitted from TRP 2). There will be no PTRS transmitted on RBsscheduled for TRP1 which is associated with the 2^(nd) TCI state.

This issue of no PTRS transmitted on RBs scheduled for TRP1 which isassociated with the 2^(nd) TCI state can be resolved if the PRG size isalso taken into account when determining the inverse frequency densityof PT-RS for multi-TRP FDM schemes 2a/2b. In one embodiment, the inversefrequency density of PT-RS is not expected to exceed PRG size forschemes 2a/2b. For instance, if PRG size is 2 for multi-TRP FDM schemes2a/2b, then the UE does not expect the thresholds ptrsthRB0 andptrsthRB1 to be configured which results in PT-RS being present on every4^(th) PRB. Alternatively stated, when PRG size is 2 for multi-TRP FDMschemes 2a/2b, the following are the only valid possibilities:

-   -   PT-RS is not present    -   PT-RS is present on every 2^(nd) PRB

In an alternate embodiment, if it is determined using NR Rel-15procedures that PT-RS is present in every N^(th) PRB, where N is greaterthan the PRG size, then the determined inverse frequency density of PTRSis overridden and N is set equal to the PRG size.

As shown in FIG. 11 , when PTRS inverse frequency density is set equalto the PRG size, PT-RS is transmitted in RBs corresponding to both the1^(st) TCI state (i.e., RBs transmitted from TRP 2) and 2^(nd) TCI state(i.e., RBs transmitted from TRP 1).

In a further embodiment, a second set of thresholds ptrsthRB0 andptrsthRB1 as used in Table 2, are signaled from the network to thecommunication device. Hence the communication can be configured with twosets of PT-RS thresholds where the first set is used for “normal” mobilebroadband services such as defined in Rel.15, while the second set isused when Scheme 2a or 2b is scheduled. Thus, depending on the servicetype (i.e. the transmission scheme), different thresholds applies indetermining the PT-RS density. This allows for increasing the PT-RSdensity (as a function of scheduled PDSCH bandwidth N_(PRB) as indicatedin the scheduling DCI) when Scheme 2a or 2b is scheduled, and use thenormal PT-RS density when Scheme 2a or 2b is not scheduled (e.g., whennormal Rel.15 PDSCH is scheduled).

TABLE 2 NR inverse frequency density of PT-RS as a function of scheduledPDSCH bandwidth when Scheme 2a or 2b is scheduled Scheduled bandwidthInverse frequency density (K_(PT,RS)) N_(PRB) < ptrsthRB2 PT-RS is notpresent ptrsthRB2 <= N_(PRB) < ptrsthRB3 present on every 2nd PRBptrsthRB3 <= N_(PRB) present on every 4th PRB

Thus, when the communication device is configured to receive a multi-TRPscheme 2a or 2b (i.e. FDM scheme) with two TCI states, the DCI indicatesthe scheduled resource blocks, which are divided into twonon-overlapping subsets. Each subset is associated with its individualTCI state, to allow transmission from two different transmission pointsrespectively. In this case, the determination of K_(PT-RS) includes atleast one of the following steps:

-   -   The scheduling bandwidth X as indicated in the DCI is modified        (e.g. reduced)    -   The inverse frequency density is reduced    -   Taking into account PRG size while determining K_(PT-RS) such        that K_(PT-RS) is not expected to exceed PRG size for schemes        2a/2b (only applicable when wideband PRG size is not        configured).

Now that the details of the schemes 2a and 2b have been described,operations of the communication device 1200 to utilize the schemes 2aand 2b (implemented using the structure of the block diagram of FIG. 12) will now be discussed with reference to the flow chart of FIG. 15according to some embodiments of inventive concepts. For example,modules may be stored in memory 1205 of FIG. 12 , and these modules mayprovide instructions so that when the instructions of a module areexecuted by respective communication device processing circuitry 1203,processing circuitry 1203 performs respective operations of the flowchart.

In block 1501 of FIG. 15 the processing circuitry 1203 may receive, viatransceiver 1201 and/or antenna(s) 1207, a higher layer configuration ofa mTRP scheme. The higher layer configuration may be a RRCconfiguration.

In block 1503, the processing circuitry 1203 may receive, viatransceiver 1201 and antenna(s) 1207, downlink control information(DCI). The DCI maybe a Format 1_1 or 1_2. The DCI may indicate a atleast two transmission points scheme for a scheduled data transmissionon physical resource blocks, for example, in the DCI the UE is indicatedwith two TCI states in a codepoint of the DCI field ‘TransmissionConfiguration Indication’. A TCI state corresponds to a transmissionpoint. Through-out the embodiments a TCI state and a transmission pointmay be used interchangeably. Similarly, the DCI may indicate a first anda second Transmission Configuration Indicator, TCI, state in one CodeDivision Multiplexing, CDM, group for a scheduled data transmission onphysical resource blocks, PRBs. The PRBs comprise at least a firstsubset of PRBs, associated with the first TCI state, and a second subsetof PRBs, associated with the second TCI state. In a preferred embodimentthe indicated scheme is FDM scheme 2a. However, other schemes such asFDM scheme 2b may also apply. The scheduled data transmission mayinclude a PDSCH transmission from a RAN node 1300 such as base station.The data transmission may also be scheduled by the DCI.

The physical resource blocks (PRBs) may include at least a first subsetsof PRBs, associated with a first transmission point, and a second subsetof PRBs, associated with a second transmission point as shown in FIGS. 8and 9 . In FIG. 8 the PRBs of the scheduled PDSCH belong to a Precodingresource block group (PRG). The scheduled bandwidth is divided into oddand even groups PRGs. The PRBs belonging to even numbered PRGs areassociated with a first transmission point, TRP1, i.e. a first TCIstate, and the PRBs belonging to odd numbered PRGs are associated with asecond transmission point, TRP 2, i.e. a second TCI state.

In block 1505, the processing circuitry 1203 may determine a first PT-RSfrequency density for the first set of PRBs based on the number of PRBsin the first set of PRBs and a second PT-RS frequency density based onthe number of PRBs in the second set of PRBs. For example, in theembodiments shown in FIGS. 8 and 9 , a PT-RS frequency density isdetermined for the PRBs associated with TRP 1 and another PT-RSfrequency density is determined for the PRBs associated with TRP 2. ThePT-RS frequency density may include the inverse frequency density.

Operations of a RAN node 1300 (implemented using the structure of FIG.13 ) will now be discussed with reference to the flow chart of FIG. 16according to some embodiments of inventive concepts. For example,modules may be stored in memory 1305 of FIG. 13 , and these modules mayprovide instructions so that when the instructions of a module areexecuted by respective RAN node processing circuitry 1303, processingcircuitry 1303 performs respective operations of the flow chart.

In block 1601, the processing circuitry 1303 may transmit, via networkinterface 1307 and/or transceiver 1301 a higher layer configuration of amTRP scheme. The higher layer configuration may be a RRC configuration.

In block 1603, the processing circuitry 1303 may transmit, via networkinterface 1307 and/or transceiver 1301, DCI to the communication device.The DCI maybe a Format 1_1 or 1_2. The DCI may indicate a at least twotransmission points scheme for a scheduled data transmission on physicalresource blocks, for example, in the DCI the UE is indicated with twoTCI states in a codepoint of the DCI field ‘Transmission ConfigurationIndication’. A TCI state corresponds to a transmission point.Through-out the embodiments a TCI state and a transmission point may beused interchangeably. Similarly, the DCI may indicate a first and asecond Transmission Configuration Indicator, TCI, state in one CodeDivision Multiplexing, CDM, group for a scheduled data transmission onphysical resource blocks, PRBs. The PRBs comprise at least a firstsubset of PRBs, associated with the first TCI state, and a second subsetof PRBs, associated with the second TCI state. In a preferred embodimentindicated scheme is FDM scheme 2a. However, other schemes such as FDMscheme 2b may also apply. The scheduled data transmission may include aPDSCH transmission from the RAN node 1300. The data transmission mayalso be scheduled by the DCI.

Thereby, the PT-RS frequency density for the first set of PRBs isobtainable based on the number of PRBs in the first set of PRBs and aPT-RS frequency density for the second set of PRBs is obtainable basedon the number of PRBs in the second set of PRBs.

FURTHER EMBODIMENTS

Further exemplary embodiments of the communication device 1200 and RANnode 1300 are described below. The various embodiments of FIGS. 17 and18 may be optional.

Turning to FIG. 17 , in block 1500, the processing circuitry 1203 mayreceive, via transceiver 1201 and antenna(s) 1207, information includinga transmission scheme. The transmission scheme can be a normal operationtransmission scheme, a scheme 2a, or a scheme 2b. The scheme 2a and thescheme 2b may be indicated by the information indicating that the schemereceives two physical downlink data channel, PDSCH, simultaneously indifferent frequency resources, where each PDSCH is associated with atransmission configuration indicator, TCI, state specified in theinformation.

Thus, the processing circuitry 1203 may determine that the transmissionscheme is a scheme receiving two physical downlink data channel, PDSCH,simultaneously in different frequency resources, where each PDSCH isassociated with a transmission configuration indicator, TCI, state. Thisindicates that the transmission scheme is scheme 2a or scheme 2b. Inblock 1502, the processing circuitry 1203 may determine if thetransmission scheme is a scheme receiving two physical downlink datachannel, PDSCH, simultaneously in different frequency resources, whereeach PDSCH is associated with a transmission configuration indicator,TCI, state specified in the information received (e.g., the transmissionscheme is scheme 2a or scheme 2b).

In block 1504, the processing circuitry 1203 may receive an indicationof a set of threshold values from a plurality of sets of thresholdvalues to use in determining the inverse frequency density describedherein. Receiving the indication may include receiving a first set ofthreshold values of the plurality of sets of threshold values responsiveto the transmission scheme being the scheme 2b. Receiving the indicationmay include receiving a second set of threshold values of the pluralityof sets of threshold values responsive to the transmission scheme beingother than the scheme 2b.

In block 1506, the processing circuitry 1203 may divide a scheduledbandwidth into odd and even groups of adjacent resource blocks to formodd precoding resource block groups, PRGs, of size N and even PRGs ofsize N.

In block 1508, the processing circuitry 1203 may determine an inversefrequency density based on a number of scheduled resource blocksspecified in the information. In one embodiment, the processingcircuitry 1203 may determine the inverse frequency density based on halfof the number of scheduled resource blocks. In one embodiment, theprocessing circuitry 1203 may determine the inverse frequency densitybased on a third of the number of scheduled resource blocks. In anotherembodiment, the processing circuitry 1203 may determine the inversefrequency density based on a number of scheduled resource blocks bycomparing a modification (e.g., ⅓, ½, etc.) of the number of scheduledresource blocks to threshold values to determine the inverse frequencydensity. In a further embodiment, the processing circuitry 1203 maydetermine the inverse frequency density based on a number of scheduledresource blocks by determining the inverse frequency density based on asubset of the scheduled resource blocks that are associated to one oftwo TCI states.

In another embodiment, the processing circuitry 1203 may determine theinverse frequency density based on a number of scheduled resource blocksby comparing the number of scheduled resource blocks to the set ofthreshold values. Responsive to the number of scheduled resource blocksbeing above a first threshold number of the set of threshold values andbelow a second threshold number of the set of threshold values, theprocessing circuitry 1203 may determine that the PT-RS is present onevery second resource block. Responsive to the number of scheduledresource blocks being above the first threshold number of the set ofthreshold values and above the second threshold number of the set ofthreshold values, the processing circuitry 1203 may determine that thePT-RS is present on every fourth resource block.

In block 1510, responsive to the transmission scheme being a scheme 2a,the processing circuitry 1203 may modify the inverse frequency densityrelative to the inverse frequency density determined to increase anumber of PT-RS samples across frequency in the scheduled resources.

In bock 1512, based on the inverse frequency density, the processingcircuitry 1203 may determine which resource blocks a subcarriercontaining PT-RS resource elements are present. For example, asdescribed above, the processing circuitry 1203 may determine a PT-RS ispresent on every second PRB or present on every fourth PRB. Thus, theprocessing circuitry 1203 may compare the number of scheduled resourceblocks to the set of threshold values. Responsive to the number ofscheduled resource blocks being above a first threshold number of theset of threshold values and below a second threshold number of the setof threshold values, the processing circuitry 1203 may determine thatthe PT-RS is present on every second resource block. Responsive to thenumber of scheduled resource blocks being above the first thresholdnumber of the set of threshold values and above the second thresholdnumber of the set of threshold values, the processing circuitry 1203 maydetermine that the PT-RS is present on every fourth resource block

The processing circuitry 1203 may determine that the PT-RS is present inevery Mth resource block. In block 1514, the processing circuitry 1203may, responsive to determining that PT-RS is present in every Mthresource block where M is greater than N, set M to be equal to size N.For example, when PRG size is 2 (i.e., the size N is 2) for multi-TRPFDM schemes 2a/2b, the following are the only valid possibilities: PT-RSis not present or PT-RS is present on every second PRB. If theprocessing circuitry 1203 determines that the PT-RS is present in everyfourth block (e.g., is present on every fourth PRB) when the PRG size is2, then the processing circuitry 1203 resets M to be 2 such that thePT-RS is present on every second PRB.

Various operations from the flow chart of FIG. 17 may be optional withrespect to some embodiments of wireless devices and related methods.Regarding methods of example embodiments 1, 12, 14, 16, and 18 (setforth below), for example, operations of blocks 1504, 1506, 1510, and1514 of FIG. 17 may be optional.

Operations of a RAN node 1300 (implemented using the structure of FIG.13 ) will now be discussed with reference to the flow chart of FIG. 18according to some embodiments of inventive concepts. For example,modules may be stored in memory 1305 of FIG. 13 , and these modules mayprovide instructions so that when the instructions of a module areexecuted by respective RAN node processing circuitry 1303, processingcircuitry 1303 performs respective operations of the flow chart.

In block 1600, the processing circuitry 1303 may determine atransmission scheme to transmit data to a communication device. In block1602, responsive to the transmission scheme being a scheme 2b where twotransmission configuration indicator, TCI, states are used, theprocessing circuitry 1303 may transmit, via network interface 1307and/or transceiver 1301 to the communication device, informationincluding a TCI state, an identification that scheme 2b is being used,and a number of resource blocks for the TCI state.

In block 1604, responsive to the transmission scheme being the scheme2b, the processing circuitry 1303 may transmit a first set of thresholdvalues to the communication device. The communication device may use thefirst set of threshold values in determining the inverse frequencyintensity.

In block 1606, responsive to the transmission scheme being a scheme 2a,may transmit, via network interface 1307 and/or transceiver 1301 to thecommunication device, information including an identification thatscheme 2a is being used, and a number of resource blocks for the scheme2a.

In block 1608, responsive to the transmission scheme being a normalscheme, the processing circuitry 1303 may transmit a second set ofthreshold values to the communication device. This allows the RAN nodeto use a different set of threshold values for scheme 2b than for normaloperation.

Various operations from the flow chart of FIG. 18 may be optional withrespect to some embodiments of RAN nodes and related methods. Regardingmethods of example embodiments 20, 22, 24, 26, and 28 (set forth below),for example, operations of blocks 1604 and 1608 of FIG. 18 may beoptional.

Example embodiments are discussed below.

-   -   1. A method in a communication device for determining resource        blocks where phase tracking reference signals, PT-RS, resource        elements are present in a communication network, the method        comprising:        -   receiving (1500) information including a transmission            scheme;        -   responsive to the transmission scheme being a scheme            receiving two physical downlink data channel, PDSCH,            simultaneously in different frequency resources, where each            PDSCH is associated with a transmission configuration            indicator, TCI, state specified in the information (1502):            -   for each PDSCH:                -   determining (1508) an inverse frequency density                    based on a number of scheduled resource blocks                    specified in the information; and                -   based on the inverse frequency density, determining                    (1512) which resource blocks a subcarrier containing                    PT-RS resource elements are present.    -   2. The method of Embodiment 1 wherein determining the inverse        frequency density based on the number of scheduled resource        blocks comprises determining the inverse frequency density based        on half of the number of scheduled resource blocks.    -   3. The method of Embodiment 1 wherein determining the inverse        frequency density based on the number of scheduled resource        blocks comprises determining the inverse frequency density based        on a third of the number of scheduled resource blocks.    -   4. The method of any of Embodiments 1-3 wherein determining the        inverse frequency density comprises comparing a modification of        the number of scheduled resource blocks to threshold values to        determine the inverse frequency density.    -   5. The method of Embodiments 1-4 wherein determining the inverse        frequency density based on the number of scheduled resource        blocks comprises determining the inverse frequency density based        on a subset of the scheduled resource blocks that are associated        to one of two TCI states.    -   6. The method of any of Embodiments 1-5, further comprising        -   receiving (1504) an indication of a set of threshold values            from a plurality of sets of threshold values to use in            determining the inverse frequency density.    -   7. The method of any of Embodiment 6 wherein determining the        inverse frequency density based on the number of scheduled        resource blocks comprises        -   comparing the number of scheduled resource blocks to the set            of threshold values;        -   responsive to the number of scheduled resource blocks being            above a first threshold number of the set of threshold            values and below a second threshold number of the set of            threshold values, determining that the PT-RS is present on            every second resource block; and        -   responsive to the number of scheduled resource blocks being            above the first threshold number of the set of threshold            values and above the second threshold number of the set of            threshold values, determining that the PT-RS is present on            every fourth resource block.    -   8. The method of any of Embodiments 6-7 wherein receiving the        indication of the set of threshold values comprises:        -   receiving a first set of threshold values of the plurality            of sets of threshold values responsive to the transmission            scheme being the scheme 2b; and        -   receiving a second set of threshold values of the plurality            of sets of threshold values responsive to the transmission            scheme being other than the scheme 2b    -   9. The method of any of Embodiments 1-6 further comprising:        -   responsive to the transmission scheme being a scheme 2a,            modifying (1510) the inverse frequency density relative to            the inverse frequency density determined to increase a            number of PT-RS samples across frequency in the scheduled            resources.    -   10. The method of any of Embodiments 1-9, further comprising:        -   dividing (1506) a scheduled bandwidth into odd and even            groups of adjacent resource blocks to form odd precoding            resource block groups, PRGs, of size N and even PRGs of size            N.    -   11. The method of any of Embodiments 1-10, further comprising:        -   responsive to determining that PT-RS is present in every Mth            resource block where M is greater than N, setting (1514) M            to be equal to size N.    -   12. A communications device (1200) comprising:        -   processing circuitry (1203); and        -   memory (1205) coupled with the processing circuitry, wherein            the memory includes instructions that when executed by the            processing circuitry causes the communication device to            perform operations comprising:            -   receiving (1500) information including a transmission                scheme;            -   responsive to the transmission scheme being a scheme                receiving two physical downlink data channel, PDSCH,                simultaneously in different frequency resources, where                each PDSCH is associated with a transmission                configuration indicator, TCI, state specified in the                information (1502):                -   for each PDSCH:                -    determining (1508) an inverse frequency density                    based on a number of scheduled resource blocks                    specified in the information; and                -    based on the inverse frequency density, determining                    (1512) which resource blocks a subcarrier containing                    PT-RS resource elements are present.    -   13. The communication device (1200) of Embodiment 12, wherein        the memory includes instructions that when executed by the        processing circuitry causes the communication device to perform        operations according to any of Embodiments 2-11.    -   14. A communication device (1200) adapted to perform operations        comprising:        -   receiving (1500) information including a transmission            scheme;        -   responsive to the transmission scheme being a scheme            receiving two physical downlink data channel, PDSCH,            simultaneously in different frequency resources, where each            PDSCH is associated with a transmission configuration            indicator, TCI, state specified in the information (1502):            -   for each PDSCH:                -   determining (1508) an inverse frequency density                    based on a number of scheduled resource blocks                    specified in the information; and                -   based on the inverse frequency density, determining                    (1512) which resource blocks a subcarrier containing                    PT-RS resource elements are present.    -   15. The communication device (1200) of Embodiment 14 adapted to        perform according to any of Embodiments 2-11.    -   16. A computer program comprising program code to be executed by        processing circuitry (1203) of a communication device (1200),        whereby execution of the program code causes the communication        device (1200) to perform operations comprising:        -   receiving (1500) information including a transmission            scheme;        -   responsive to the transmission scheme being a scheme            receiving two physical downlink data channel, PDSCH,            simultaneously in different frequency resources, where each            PDSCH is associated with a transmission configuration            indicator, TCI, state specified in the information (1502):            -   for each PDSCH:                -   determining (1508) an inverse frequency density                    based on a number of scheduled resource blocks                    specified in the information; and                -   based on the inverse frequency density, determining                    (1512) which resource blocks a subcarrier containing                    PT-RS resource elements are present.    -   17. The computer program of Embodiment 16 whereby execution of        the program code causes the communication device (1200) to        perform operations according to any of Embodiments 2-11.    -   18. A computer program product comprising a non-transitory        storage medium including program code to be executed by        processing circuitry (1203) of a communication device (1200),        whereby execution of the program code causes the communication        device (1200) to perform operations comprising:        -   receiving (1500) information including a transmission            scheme;        -   responsive to the transmission scheme being a scheme            receiving two physical downlink data channel, PDSCH,            simultaneously in different frequency resources, where each            PDSCH is associated with a transmission configuration            indicator, TCI, state specified in the information (1502):            -   for each PDSCH:                -   determining (1508) an inverse frequency density                    based on a number of scheduled resource blocks                    specified in the information; and                -   based on the inverse frequency density, determining                    (1512) which resource blocks a subcarrier containing                    PT-RS resource elements are present.    -   19. The computer program product of Embodiment 18 whereby        execution of the program code causes the communication device        (1200) to perform operations according to any of embodiments        2-11.    -   20. A method of operating a radio access network node, RAN,        (1300) in a communication network, the method comprising:        -   determining (1600) a transmission scheme to transmit data to            a communication device;        -   responsive to the transmission scheme being a scheme 2b            where two transmission configuration indicator, TCI, states            are used, transmitting (1602), to the communication device,            information including a TCI state, an identification that            scheme 2b is being used, and a number of resource blocks for            the TCI state; and        -   responsive to the transmission scheme being a scheme 2a,            transmitting (1606), to the communication device,            information including an identification that scheme 2a is            being used, and a number of resource blocks for the scheme            2a.    -   21. The method of Embodiment 19, further comprising:        -   responsive to the transmission scheme being the scheme 2b,            transmitting (1604) a first set of threshold values to the            communication device; and        -   responsive to the transmission scheme being a normal scheme,            transmitting (1608) a second set of threshold values to the            communication device.    -   22. A radio access network, RAN, node (1300) comprising:        -   processing circuitry (1303); and        -   memory (1305) coupled with the processing circuitry, wherein            the memory includes instructions that when executed by the            processing circuitry causes the RAN node to perform            operations comprising:        -   determining (1600) a transmission scheme to transmit data to            a communication device;        -   responsive to the transmission scheme being a scheme 2b            where two transmission configuration indicator, TCI, states            are used, transmitting (1602), to the communication device,            information including a TCI state, an identification that            scheme 2b is being used, and a number of resource blocks for            the TCI state; and        -   responsive to the transmission scheme being a scheme 2a,            transmitting (1604), to the communication device,            information including an identification that scheme 2a is            being used, and a number of resource blocks for the scheme            2a.    -   23. The RAN node of Embodiment 22 wherein the memory includes        further instructions that when executed by the processing        circuitry causes the RAN node to perform operations according to        Embodiment 21.    -   24. A radio access network, RAN, node (1300) adapted to perform        operations comprising:        -   determining (1600) a transmission scheme to transmit data to            a communication device;        -   responsive to the transmission scheme being a scheme 2b            where two transmission configuration indicator, TCI, states            are used, transmitting (1602), to the communication device,            information including a TCI state, an identification that            scheme 2b is being used, and a number of resource blocks for            the TCI state; and        -   responsive to the transmission scheme being a scheme 2a,            transmitting (1604), to the communication device,            information including an identification that scheme 2a is            being used, and a number of resource blocks for the scheme            2a.    -   25. The RAN node (1300) of Embodiment 24 wherein the RAN node is        further adapted to perform according to Embodiment 21.    -   26. A computer program comprising program code to be executed by        processing circuitry (1303) of a radio access network, RAN, node        (1300), whereby execution of the program code causes the RAN        node (1300) to perform operations comprising:        -   determining (1600) a transmission scheme to transmit data to            a communication device;        -   responsive to the transmission scheme being a scheme 2b            where two transmission configuration indicator, TCI, states            are used, transmitting (1602), to the communication device,            information including a TCI state, an identification that            scheme 2b is being used, and a number of resource blocks for            the TCI state; and        -   responsive to the transmission scheme being a scheme 2a,            transmitting (1604), to the communication device,            information including an identification that scheme 2a is            being used, and a number of resource blocks for the scheme            2a.    -   27. The computer program of Embodiment 26 whereby execution of        the program code causes the RAN node (1300) to perform further        operations according to embodiment 21.    -   28. A computer program product comprising a non-transitory        storage medium including program code to be executed by        processing circuitry (1303) of a radio access network, RAN, node        (1300), whereby execution of the program code causes the RAN        node (1300) to perform operations comprising:        -   determining (1600) a transmission scheme to transmit data to            a communication device;        -   responsive to the transmission scheme being a scheme 2b            where two transmission configuration indicator, TCI, states            are used, transmitting (1602), to the communication device,            information including a TCI state, an identification that            scheme 2b is being used, and a number of resource blocks for            the TCI state; and        -   responsive to the transmission scheme being a scheme 2a,            transmitting (1604), to the communication device,            information including an identification that scheme 2a is            being used, and a number of resource blocks for the scheme            2a.    -   29. The computer program product of Embodiment 28 whereby        execution of the program code causes the RAN node (1300) to        perform operations according to embodiment 21.

Explanations are provided below for various abbreviations/acronyms usedin the present disclosure.

Abbreviation Explanation SCS subcarrier spacing NR new radio RB resourceblock OFDM Orthogonal Frequency Division Multiplexing CP cyclic prefixDFT discrete Fourier transform PDCCH physical downlink control channelPDCH physical data channel PDSCH physical downlink data channel PUSCHphysical uplink data channel DCI downlink control information TDRA timedomain resource assignment RRC radio resource control SLIV start andlength indicator DM-RS demodulation reference signal TCI transmissionconfiguration indicator RE resource element QCL quasi co-located CSI-RSchannel-state information reference signal PT-RS phase trackingreference signal TRP transmission point FDM frequency divisionmultiplexed PRG precoding resource block group

References are identified below.

3GPP TS 38.214 v15.6.0-3rd Generation Partnership Project; TechnicalSpecification Group Radio Access Network; NR; Physical layer proceduresfor data (Release 15)

Additional explanation is provided below.

Generally, all terms used herein are to be interpreted according totheir ordinary meaning in the relevant technical field, unless adifferent meaning is clearly given and/or is implied from the context inwhich it is used. All references to a/an/the element, apparatus,component, means, step, etc. are to be interpreted openly as referringto at least one instance of the element, apparatus, component, means,step, etc., unless explicitly stated otherwise. The steps of any methodsdisclosed herein do not have to be performed in the exact orderdisclosed, unless a step is explicitly described as following orpreceding another step and/or where it is implicit that a step mustfollow or precede another step. Any feature of any of the embodimentsdisclosed herein may be applied to any other embodiment, whereverappropriate. Likewise, any advantage of any of the embodiments may applyto any other embodiments, and vice versa. Other objectives, features andadvantages of the enclosed embodiments will be apparent from thefollowing description.

Some of the embodiments contemplated herein will now be described morefully with reference to the accompanying drawings. Other embodiments,however, are contained within the scope of the subject matter disclosedherein, the disclosed subject matter should not be construed as limitedto only the embodiments set forth herein; rather, these embodiments areprovided by way of example to convey the scope of the subject matter tothose skilled in the art.

FIG. 21 illustrates a wireless network in accordance with someembodiments.

Although the subject matter described herein may be implemented in anyappropriate type of system using any suitable components, theembodiments disclosed herein are described in relation to a wirelessnetwork, such as the example wireless network illustrated in FIG. 21 .For simplicity, the wireless network of FIG. 21 only depicts network4106, network nodes 4160 and 4160 b, and WDs 4110, 4110 b, and 4110 c(also referred to as mobile terminals). In practice, a wireless networkmay further include any additional elements suitable to supportcommunication between wireless devices or between a wireless device andanother communication device, such as a landline telephone, a serviceprovider, or any other network node or end device. Of the illustratedcomponents, network node 4160 and wireless device (WD) 4110 are depictedwith additional detail. The wireless network may provide communicationand other types of services to one or more wireless devices tofacilitate the wireless devices' access to and/or use of the servicesprovided by, or via, the wireless network.

The wireless network may comprise and/or interface with any type ofcommunication, telecommunication, data, cellular, and/or radio networkor other similar type of system. In some embodiments, the wirelessnetwork may be configured to operate according to specific standards orother types of predefined rules or procedures. Thus, particularembodiments of the wireless network may implement communicationstandards, such as Global System for Mobile Communications (GSM),Universal Mobile Telecommunications System (UMTS), Long Term Evolution(LTE), and/or other suitable 2G, 3G, 4G, or 5G standards; wireless localarea network (WLAN) standards, such as the IEEE 802.11 standards; and/orany other appropriate wireless communication standard, such as theWorldwide Interoperability for Microwave Access (WiMax), Bluetooth,Z-Wave and/or ZigBee standards.

Network 4106 may comprise one or more backhaul networks, core networks,IP networks, public switched telephone networks (PSTNs), packet datanetworks, optical networks, wide-area networks (WANs), local areanetworks (LANs), wireless local area networks (WLANs), wired networks,wireless networks, metropolitan area networks, and other networks toenable communication between devices.

Network node 4160 and WD 4110 comprise various components described inmore detail below. These components work together in order to providenetwork node and/or wireless device functionality, such as providingwireless connections in a wireless network. In different embodiments,the wireless network may comprise any number of wired or wirelessnetworks, network nodes, base stations, controllers, wireless devices,relay stations, and/or any other components or systems that mayfacilitate or participate in the communication of data and/or signalswhether via wired or wireless connections.

As used herein, network node refers to equipment capable, configured,arranged and/or operable to communicate directly or indirectly with awireless device and/or with other network nodes or equipment in thewireless network to enable and/or provide wireless access to thewireless device and/or to perform other functions (e.g., administration)in the wireless network. Examples of network nodes include, but are notlimited to, access points (APs) (e.g., radio access points), basestations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs(eNBs) and NR NodeBs (gNBs)). Base stations may be categorized based onthe amount of coverage they provide (or, stated differently, theirtransmit power level) and may then also be referred to as femto basestations, pico base stations, micro base stations, or macro basestations. A base station may be a relay node or a relay donor nodecontrolling a relay. A network node may also include one or more (orall) parts of a distributed radio base station such as centralizeddigital units and/or remote radio units (RRUs), sometimes referred to asRemote Radio Heads (RRHs). Such remote radio units may or may not beintegrated with an antenna as an antenna integrated radio. Parts of adistributed radio base station may also be referred to as nodes in adistributed antenna system (DAS). Yet further examples of network nodesinclude multi-standard radio (MSR) equipment such as MSR BSs, networkcontrollers such as radio network controllers (RNCs) or base stationcontrollers (BSCs), base transceiver stations (BTSs), transmissionpoints, transmission nodes, multi-cell/multicast coordination entities(MCEs), core network nodes (e.g., MSCs, MMEs), O&M nodes, OSS nodes, SONnodes, positioning nodes (e.g., E-SMLCs), and/or MDTs. As anotherexample, a network node may be a virtual network node as described inmore detail below. More generally, however, network nodes may representany suitable device (or group of devices) capable, configured, arranged,and/or operable to enable and/or provide a wireless device with accessto the wireless network or to provide some service to a wireless devicethat has accessed the wireless network.

In FIG. 21 , network node 4160 includes processing circuitry 4170,device readable medium 4180, interface 4190, auxiliary equipment 4184,power source 4186, power circuitry 4187, and antenna 4162. Althoughnetwork node 4160 illustrated in the example wireless network of FIG.211 may represent a device that includes the illustrated combination ofhardware components, other embodiments may comprise network nodes withdifferent combinations of components. It is to be understood that anetwork node comprises any suitable combination of hardware and/orsoftware needed to perform the tasks, features, functions and methodsdisclosed herein. Moreover, while the components of network node 4160are depicted as single boxes located within a larger box, or nestedwithin multiple boxes, in practice, a network node may comprise multipledifferent physical components that make up a single illustratedcomponent (e.g., device readable medium 4180 may comprise multipleseparate hard drives as well as multiple RAM modules).

Similarly, network node 4160 may be composed of multiple physicallyseparate components (e.g., a NodeB component and a RNC component, or aBTS component and a BSC component, etc.), which may each have their ownrespective components. In certain scenarios in which network node 4160comprises multiple separate components (e.g., BTS and BSC components),one or more of the separate components may be shared among severalnetwork nodes. For example, a single RNC may control multiple NodeB's.In such a scenario, each unique NodeB and RNC pair, may in someinstances be considered a single separate network node. In someembodiments, network node 4160 may be configured to support multipleradio access technologies (RATs). In such embodiments, some componentsmay be duplicated (e.g., separate device readable medium 4180 for thedifferent RATs) and some components may be reused (e.g., the sameantenna 4162 may be shared by the RATs). Network node 4160 may alsoinclude multiple sets of the various illustrated components fordifferent wireless technologies integrated into network node 4160, suchas, for example, GSM, WCDMA, LTE, NR, WiFi, or Bluetooth wirelesstechnologies. These wireless technologies may be integrated into thesame or different chip or set of chips and other components withinnetwork node 4160.

Processing circuitry 4170 is configured to perform any determining,calculating, or similar operations (e.g., certain obtaining operations)described herein as being provided by a network node. These operationsperformed by processing circuitry 4170 may include processinginformation obtained by processing circuitry 4170 by, for example,converting the obtained information into other information, comparingthe obtained information or converted information to information storedin the network node, and/or performing one or more operations based onthe obtained information or converted information, and as a result ofsaid processing making a determination.

Processing circuitry 4170 may comprise a combination of one or more of amicroprocessor, controller, microcontroller, central processing unit,digital signal processor, application-specific integrated circuit, fieldprogrammable gate array, or any other suitable computing device,resource, or combination of hardware, software and/or encoded logicoperable to provide, either alone or in conjunction with other networknode 4160 components, such as device readable medium 4180, network node4160 functionality. For example, processing circuitry 4170 may executeinstructions stored in device readable medium 4180 or in memory withinprocessing circuitry 4170. Such functionality may include providing anyof the various wireless features, functions, or benefits discussedherein. In some embodiments, processing circuitry 4170 may include asystem on a chip (SOC).

In some embodiments, processing circuitry 4170 may include one or moreof radio frequency (RF) transceiver circuitry 4172 and basebandprocessing circuitry 4174. In some embodiments, radio frequency (RF)transceiver circuitry 4172 and baseband processing circuitry 4174 may beon separate chips (or sets of chips), boards, or units, such as radiounits and digital units. In alternative embodiments, part or all of RFtransceiver circuitry 4172 and baseband processing circuitry 4174 may beon the same chip or set of chips, boards, or units

In certain embodiments, some or all of the functionality describedherein as being provided by a network node, base station, eNB or othersuch network device may be performed by processing circuitry 4170executing instructions stored on device readable medium 4180 or memorywithin processing circuitry 4170. In alternative embodiments, some orall of the functionality may be provided by processing circuitry 4170without executing instructions stored on a separate or discrete devicereadable medium, such as in a hard-wired manner In any of thoseembodiments, whether executing instructions stored on a device readablestorage medium or not, processing circuitry 4170 can be configured toperform the described functionality. The benefits provided by suchfunctionality are not limited to processing circuitry 4170 alone or toother components of network node 4160, but are enjoyed by network node4160 as a whole, and/or by end users and the wireless network generally.

Device readable medium 4180 may comprise any form of volatile ornon-volatile computer readable memory including, without limitation,persistent storage, solid-state memory, remotely mounted memory,magnetic media, optical media, random access memory (RAM), read-onlymemory (ROM), mass storage media (for example, a hard disk), removablestorage media (for example, a flash drive, a Compact Disk (CD) or aDigital Video Disk (DVD)), and/or any other volatile or non-volatile,non-transitory device readable and/or computer-executable memory devicesthat store information, data, and/or instructions that may be used byprocessing circuitry 4170. Device readable medium 4180 may store anysuitable instructions, data or information, including a computerprogram, software, an application including one or more of logic, rules,code, tables, etc. and/or other instructions capable of being executedby processing circuitry 4170 and, utilized by network node 4160. Devicereadable medium 4180 may be used to store any calculations made byprocessing circuitry 4170 and/or any data received via interface 4190.In some embodiments, processing circuitry 4170 and device readablemedium 4180 may be considered to be integrated.

Interface 4190 is used in the wired or wireless communication ofsignalling and/or data between network node 4160, network 4106, and/orWDs 4110. As illustrated, interface 4190 comprises port(s)/terminal(s)4194 to send and receive data, for example to and from network 4106 overa wired connection. Interface 4190 also includes radio front endcircuitry 4192 that may be coupled to, or in certain embodiments a partof, antenna 4162. Radio front end circuitry 4192 comprises filters 4198and amplifiers 4196. Radio front end circuitry 4192 may be connected toantenna 4162 and processing circuitry 4170. Radio front end circuitrymay be configured to condition signals communicated between antenna 4162and processing circuitry 4170. Radio front end circuitry 4192 mayreceive digital data that is to be sent out to other network nodes orWDs via a wireless connection. Radio front end circuitry 4192 mayconvert the digital data into a radio signal having the appropriatechannel and bandwidth parameters using a combination of filters 4198and/or amplifiers 4196. The radio signal may then be transmitted viaantenna 4162. Similarly, when receiving data, antenna 4162 may collectradio signals which are then converted into digital data by radio frontend circuitry 4192. The digital data may be passed to processingcircuitry 4170. In other embodiments, the interface may comprisedifferent components and/or different combinations of components.

In certain alternative embodiments, network node 4160 may not includeseparate radio front end circuitry 4192, instead, processing circuitry4170 may comprise radio front end circuitry and may be connected toantenna 4162 without separate radio front end circuitry 4192. Similarly,in some embodiments, all or some of RF transceiver circuitry 4172 may beconsidered a part of interface 4190. In still other embodiments,interface 4190 may include one or more ports or terminals 4194, radiofront end circuitry 4192, and RF transceiver circuitry 4172, as part ofa radio unit (not shown), and interface 4190 may communicate withbaseband processing circuitry 4174, which is part of a digital unit (notshown).

Antenna 4162 may include one or more antennas, or antenna arrays,configured to send and/or receive wireless signals. Antenna 4162 may becoupled to radio front end circuitry 4190 and may be any type of antennacapable of transmitting and receiving data and/or signals wirelessly. Insome embodiments, antenna 4162 may comprise one or moreomni-directional, sector or panel antennas operable to transmit/receiveradio signals between, for example, 2 GHz and 66 GHz. Anomni-directional antenna may be used to transmit/receive radio signalsin any direction, a sector antenna may be used to transmit/receive radiosignals from devices within a particular area, and a panel antenna maybe a line of sight antenna used to transmit/receive radio signals in arelatively straight line. In some instances, the use of more than oneantenna may be referred to as MIMO. In certain embodiments, antenna 4162may be separate from network node 4160 and may be connectable to networknode 4160 through an interface or port.

Antenna 4162, interface 4190, and/or processing circuitry 4170 may beconfigured to perform any receiving operations and/or certain obtainingoperations described herein as being performed by a network node. Anyinformation, data and/or signals may be received from a wireless device,another network node and/or any other network equipment. Similarly,antenna 4162, interface 4190, and/or processing circuitry 4170 may beconfigured to perform any transmitting operations described herein asbeing performed by a network node. Any information, data and/or signalsmay be transmitted to a wireless device, another network node and/or anyother network equipment.

Power circuitry 4187 may comprise, or be coupled to, power managementcircuitry and is configured to supply the components of network node4160 with power for performing the functionality described herein. Powercircuitry 4187 may receive power from power source 4186. Power source4186 and/or power circuitry 4187 may be configured to provide power tothe various components of network node 4160 in a form suitable for therespective components (e.g., at a voltage and current level needed foreach respective component). Power source 4186 may either be included in,or external to, power circuitry 4187 and/or network node 4160. Forexample, network node 4160 may be connectable to an external powersource (e.g., an electricity outlet) via an input circuitry or interfacesuch as an electrical cable, whereby the external power source suppliespower to power circuitry 4187. As a further example, power source 4186may comprise a source of power in the form of a battery or battery packwhich is connected to, or integrated in, power circuitry 4187. Thebattery may provide backup power should the external power source fail.Other types of power sources, such as photovoltaic devices, may also beused.

Alternative embodiments of network node 4160 may include additionalcomponents beyond those shown in FIG. 21 that may be responsible forproviding certain aspects of the network node's functionality, includingany of the functionality described herein and/or any functionalitynecessary to support the subject matter described herein. For example,network node 4160 may include user interface equipment to allow input ofinformation into network node 4160 and to allow output of informationfrom network node 4160. This may allow a user to perform diagnostic,maintenance, repair, and other administrative functions for network node4160.

As used herein, wireless device (WD) refers to a device capable,configured, arranged and/or operable to communicate wirelessly withnetwork nodes and/or other wireless devices. Unless otherwise noted, theterm WD may be used interchangeably herein with user equipment (UE).Communicating wirelessly may involve transmitting and/or receivingwireless signals using electromagnetic waves, radio waves, infraredwaves, and/or other types of signals suitable for conveying informationthrough air. In some embodiments, a WD may be configured to transmitand/or receive information without direct human interaction. Forinstance, a WD may be designed to transmit information to a network on apredetermined schedule, when triggered by an internal or external event,or in response to requests from the network. Examples of a WD include,but are not limited to, a smart phone, a mobile phone, a cell phone, avoice over IP (VoIP) phone, a wireless local loop phone, a desktopcomputer, a personal digital assistant (PDA), a wireless cameras, agaming console or device, a music storage device, a playback appliance,a wearable terminal device, a wireless endpoint, a mobile station, atablet, a laptop, a laptop-embedded equipment (LEE), a laptop-mountedequipment (LME), a smart device, a wireless customer-premise equipment(CPE). a vehicle-mounted wireless terminal device, etc. A WD may supportdevice-to-device (D2D) communication, for example by implementing a 3GPPstandard for sidelink communication, vehicle-to-vehicle (V2V),vehicle-to-infrastructure (V2I), vehicle-to-everything (V2X) and may inthis case be referred to as a D2D communication device. As yet anotherspecific example, in an Internet of Things (IoT) scenario, a WD mayrepresent a machine or other device that performs monitoring and/ormeasurements, and transmits the results of such monitoring and/ormeasurements to another WD and/or a network node. The WD may in thiscase be a machine-to-machine (M2M) device, which may in a 3GPP contextbe referred to as an MTC device. As one particular example, the WD maybe a UE implementing the 3GPP narrow band internet of things (NB-IoT)standard. Particular examples of such machines or devices are sensors,metering devices such as power meters, industrial machinery, or home orpersonal appliances (e.g. refrigerators, televisions, etc.) personalwearables (e.g., watches, fitness trackers, etc.). In other scenarios, aWD may represent a vehicle or other equipment that is capable ofmonitoring and/or reporting on its operational status or other functionsassociated with its operation. A WD as described above may represent theendpoint of a wireless connection, in which case the device may bereferred to as a wireless terminal. Furthermore, a WD as described abovemay be mobile, in which case it may also be referred to as a mobiledevice or a mobile terminal.

As illustrated, wireless device 4110 includes antenna 4111, interface4114, processing circuitry 4120, device readable medium 4130, userinterface equipment 4132, auxiliary equipment 4134, power source 4136and power circuitry 4137. WD 4110 may include multiple sets of one ormore of the illustrated components for different wireless technologiessupported by WD 4110, such as, for example, GSM, WCDMA, LTE, NR, WiFi,WiMAX, or Bluetooth wireless technologies, just to mention a few. Thesewireless technologies may be integrated into the same or different chipsor set of chips as other components within WD 4110.

Antenna 4111 may include one or more antennas or antenna arrays,configured to send and/or receive wireless signals, and is connected tointerface 4114. In certain alternative embodiments, antenna 4111 may beseparate from WD 4110 and be connectable to WD 4110 through an interfaceor port. Antenna 4111, interface 4114, and/or processing circuitry 4120may be configured to perform any receiving or transmitting operationsdescribed herein as being performed by a WD. Any information, dataand/or signals may be received from a network node and/or another WD. Insome embodiments, radio front end circuitry and/or antenna 4111 may beconsidered an interface.

As illustrated, interface 4114 comprises radio front end circuitry 4112and antenna 4111. Radio front end circuitry 4112 comprise one or morefilters 4118 and amplifiers 4116. Radio front end circuitry 4114 isconnected to antenna 4111 and processing circuitry 4120, and isconfigured to condition signals communicated between antenna 4111 andprocessing circuitry 4120. Radio front end circuitry 4112 may be coupledto or a part of antenna 4111. In some embodiments, WD 4110 may notinclude separate radio front end circuitry 4112; rather, processingcircuitry 4120 may comprise radio front end circuitry and may beconnected to antenna 4111. Similarly, in some embodiments, some or allof RF transceiver circuitry 4122 may be considered a part of interface4114. Radio front end circuitry 4112 may receive digital data that is tobe sent out to other network nodes or WDs via a wireless connection.Radio front end circuitry 4112 may convert the digital data into a radiosignal having the appropriate channel and bandwidth parameters using acombination of filters 4118 and/or amplifiers 4116. The radio signal maythen be transmitted via antenna 4111. Similarly, when receiving data,antenna 4111 may collect radio signals which are then converted intodigital data by radio front end circuitry 4112. The digital data may bepassed to processing circuitry 4120. In other embodiments, the interfacemay comprise different components and/or different combinations ofcomponents.

Processing circuitry 4120 may comprise a combination of one or more of amicroprocessor, controller, microcontroller, central processing unit,digital signal processor, application-specific integrated circuit, fieldprogrammable gate array, or any other suitable computing device,resource, or combination of hardware, software, and/or encoded logicoperable to provide, either alone or in conjunction with other WD 4110components, such as device readable medium 4130, WD 4110 functionality.Such functionality may include providing any of the various wirelessfeatures or benefits discussed herein. For example, processing circuitry4120 may execute instructions stored in device readable medium 4130 orin memory within processing circuitry 4120 to provide the functionalitydisclosed herein.

As illustrated, processing circuitry 4120 includes one or more of RFtransceiver circuitry 4122, baseband processing circuitry 4124, andapplication processing circuitry 4126. In other embodiments, theprocessing circuitry may comprise different components and/or differentcombinations of components. In certain embodiments processing circuitry4120 of WD 4110 may comprise a SOC. In some embodiments, RF transceivercircuitry 4122, baseband processing circuitry 4124, and applicationprocessing circuitry 4126 may be on separate chips or sets of chips. Inalternative embodiments, part or all of baseband processing circuitry4124 and application processing circuitry 4126 may be combined into onechip or set of chips, and RF transceiver circuitry 4122 may be on aseparate chip or set of chips. In still alternative embodiments, part orall of RF transceiver circuitry 4122 and baseband processing circuitry4124 may be on the same chip or set of chips, and application processingcircuitry 4126 may be on a separate chip or set of chips. In yet otheralternative embodiments, part or all of RF transceiver circuitry 4122,baseband processing circuitry 4124, and application processing circuitry4126 may be combined in the same chip or set of chips. In someembodiments, RF transceiver circuitry 4122 may be a part of interface4114. RF transceiver circuitry 4122 may condition RF signals forprocessing circuitry 4120.

In certain embodiments, some or all of the functionality describedherein as being performed by a WD may be provided by processingcircuitry 4120 executing instructions stored on device readable medium4130, which in certain embodiments may be a computer-readable storagemedium. In alternative embodiments, some or all of the functionality maybe provided by processing circuitry 4120 without executing instructionsstored on a separate or discrete device readable storage medium, such asin a hard-wired manner In any of those particular embodiments, whetherexecuting instructions stored on a device readable storage medium ornot, processing circuitry 4120 can be configured to perform thedescribed functionality. The benefits provided by such functionality arenot limited to processing circuitry 4120 alone or to other components ofWD 4110, but are enjoyed by WD 4110 as a whole, and/or by end users andthe wireless network generally.

Processing circuitry 4120 may be configured to perform any determining,calculating, or similar operations (e.g., certain obtaining operations)described herein as being performed by a WD. These operations, asperformed by processing circuitry 4120, may include processinginformation obtained by processing circuitry 4120 by, for example,converting the obtained information into other information, comparingthe obtained information or converted information to information storedby WD 4110, and/or performing one or more operations based on theobtained information or converted information, and as a result of saidprocessing making a determination.

Device readable medium 4130 may be operable to store a computer program,software, an application including one or more of logic, rules, code,tables, etc. and/or other instructions capable of being executed byprocessing circuitry 4120. Device readable medium 4130 may includecomputer memory (e.g., Random Access Memory (RAM) or Read Only Memory(ROM)), mass storage media (e.g., a hard disk), removable storage media(e.g., a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or anyother volatile or non-volatile, non-transitory device readable and/orcomputer executable memory devices that store information, data, and/orinstructions that may be used by processing circuitry 4120. In someembodiments, processing circuitry 4120 and device readable medium 4130may be considered to be integrated.

User interface equipment 4132 may provide components that allow for ahuman user to interact with WD 4110. Such interaction may be of manyforms, such as visual, audial, tactile, etc. User interface equipment4132 may be operable to produce output to the user and to allow the userto provide input to WD 4110. The type of interaction may vary dependingon the type of user interface equipment 4132 installed in WD 4110. Forexample, if WD 4110 is a smart phone, the interaction may be via a touchscreen; if WD 4110 is a smart meter, the interaction may be through ascreen that provides usage (e.g., the number of gallons used) or aspeaker that provides an audible alert (e.g., if smoke is detected).User interface equipment 4132 may include input interfaces, devices andcircuits, and output interfaces, devices and circuits. User interfaceequipment 4132 is configured to allow input of information into WD 4110,and is connected to processing circuitry 4120 to allow processingcircuitry 4120 to process the input information. User interfaceequipment 4132 may include, for example, a microphone, a proximity orother sensor, keys/buttons, a touch display, one or more cameras, a USBport, or other input circuitry. User interface equipment 4132 is alsoconfigured to allow output of information from WD 4110, and to allowprocessing circuitry 4120 to output information from WD 4110. Userinterface equipment 4132 may include, for example, a speaker, a display,vibrating circuitry, a USB port, a headphone interface, or other outputcircuitry. Using one or more input and output interfaces, devices, andcircuits, of user interface equipment 4132, WD 4110 may communicate withend users and/or the wireless network, and allow them to benefit fromthe functionality described herein.

Auxiliary equipment 4134 is operable to provide more specificfunctionality which may not be generally performed by WDs. This maycomprise specialized sensors for doing measurements for variouspurposes, interfaces for additional types of communication such as wiredcommunications etc. The inclusion and type of components of auxiliaryequipment 4134 may vary depending on the embodiment and/or scenario.

Power source 4136 may, in some embodiments, be in the form of a batteryor battery pack. Other types of power sources, such as an external powersource (e.g., an electricity outlet), photovoltaic devices or powercells, may also be used. WD 4110 may further comprise power circuitry4137 for delivering power from power source 4136 to the various parts ofWD 4110 which need power from power source 4136 to carry out anyfunctionality described or indicated herein. Power circuitry 4137 may incertain embodiments comprise power management circuitry. Power circuitry4137 may additionally or alternatively be operable to receive power froman external power source; in which case WD 4110 may be connectable tothe external power source (such as an electricity outlet) via inputcircuitry or an interface such as an electrical power cable. Powercircuitry 4137 may also in certain embodiments be operable to deliverpower from an external power source to power source 4136. This may be,for example, for the charging of power source 4136. Power circuitry 4137may perform any formatting, converting, or other modification to thepower from power source 4136 to make the power suitable for therespective components of WD 4110 to which power is supplied.

FIG. 22 illustrates a user Equipment in accordance with someembodiments.

FIG. 22 illustrates one embodiment of a UE in accordance with variousaspects described herein. As used herein, a user equipment or UE may notnecessarily have a user in the sense of a human user who owns and/oroperates the relevant device. Instead, a UE may represent a device thatis intended for sale to, or operation by, a human user but which maynot, or which may not initially, be associated with a specific humanuser (e.g., a smart sprinkler controller). Alternatively, a UE mayrepresent a device that is not intended for sale to, or operation by, anend user but which may be associated with or operated for the benefit ofa user (e.g., a smart power meter). UE 42200 may be any UE identified bythe 3rd Generation Partnership Project (3GPP), including a NB-IoT UE, amachine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.UE 4200, as illustrated in FIG. 22 , is one example of a WD configuredfor communication in accordance with one or more communication standardspromulgated by the 3rd Generation Partnership Project (3GPP), such as3GPP's GSM, UMTS, LTE, and/or 5G standards. As mentioned previously, theterm WD and UE may be used interchangeable. Accordingly, although FIG.22 is a UE, the components discussed herein are equally applicable to aWD, and vice-versa.

In FIG. 22 , UE 4200 includes processing circuitry 4201 that isoperatively coupled to input/output interface 4205, radio frequency (RF)interface 4209, network connection interface 4211, memory 4215 includingrandom access memory (RAM) 4217, read-only memory (ROM) 4219, andstorage medium 4221 or the like, communication subsystem 4231, powersource 4233, and/or any other component, or any combination thereof.Storage medium 4221 includes operating system 4223, application program4225, and data 4227. In other embodiments, storage medium 4221 mayinclude other similar types of information. Certain UEs may utilize allof the components shown in FIG. 22 , or only a subset of the components.The level of integration between the components may vary from one UE toanother UE. Further, certain UEs may contain multiple instances of acomponent, such as multiple processors, memories, transceivers,transmitters, receivers, etc.

In FIG. 22 , processing circuitry 4201 may be configured to processcomputer instructions and data. Processing circuitry 4201 may beconfigured to implement any sequential state machine operative toexecute machine instructions stored as machine-readable computerprograms in the memory, such as one or more hardware-implemented statemachines (e.g., in discrete logic, FPGA, ASIC, etc.); programmable logictogether with appropriate firmware; one or more stored program,general-purpose processors, such as a microprocessor or Digital SignalProcessor (DSP), together with appropriate software; or any combinationof the above. For example, the processing circuitry 4201 may include twocentral processing units (CPUs). Data may be information in a formsuitable for use by a computer.

In the depicted embodiment, input/output interface 4205 may beconfigured to provide a communication interface to an input device,output device, or input and output device. UE 4200 may be configured touse an output device via input/output interface 4205. An output devicemay use the same type of interface port as an input device. For example,a USB port may be used to provide input to and output from UE 4200. Theoutput device may be a speaker, a sound card, a video card, a display, amonitor, a printer, an actuator, an emitter, a smartcard, another outputdevice, or any combination thereof. UE 4200 may be configured to use aninput device via input/output interface 4205 to allow a user to captureinformation into UE 4200. The input device may include a touch-sensitiveor presence-sensitive display, a camera (e.g., a digital camera, adigital video camera, a web camera, etc.), a microphone, a sensor, amouse, a trackball, a directional pad, a trackpad, a scroll wheel, asmartcard, and the like. The presence-sensitive display may include acapacitive or resistive touch sensor to sense input from a user. Asensor may be, for instance, an accelerometer, a gyroscope, a tiltsensor, a force sensor, a magnetometer, an optical sensor, a proximitysensor, another like sensor, or any combination thereof. For example,the input device may be an accelerometer, a magnetometer, a digitalcamera, a microphone, and an optical sensor.

In FIG. 22 , RF interface 4209 may be configured to provide acommunication interface to RF components such as a transmitter, areceiver, and an antenna. Network connection interface 4211 may beconfigured to provide a communication interface to network 4243 a.Network 4243 a may encompass wired and/or wireless networks such as alocal-area network (LAN), a wide-area network (WAN), a computer network,a wireless network, a telecommunications network, another like networkor any combination thereof. For example, network 4243 a may comprise aWi-Fi network. Network connection interface 4211 may be configured toinclude a receiver and a transmitter interface used to communicate withone or more other devices over a communication network according to oneor more communication protocols, such as Ethernet, TCP/IP, SONET, ATM,or the like. Network connection interface 4211 may implement receiverand transmitter functionality appropriate to the communication networklinks (e.g., optical, electrical, and the like). The transmitter andreceiver functions may share circuit components, software or firmware,or alternatively may be implemented separately.

RAM 4217 may be configured to interface via bus 4202 to processingcircuitry 4201 to provide storage or caching of data or computerinstructions during the execution of software programs such as theoperating system, application programs, and device drivers. ROM 4219 maybe configured to provide computer instructions or data to processingcircuitry 4201. For example, ROM 4219 may be configured to storeinvariant low-level system code or data for basic system functions suchas basic input and output (I/O), startup, or reception of keystrokesfrom a keyboard that are stored in a non-volatile memory. Storage medium4221 may be configured to include memory such as RAM, ROM, programmableread-only memory (PROM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), magneticdisks, optical disks, floppy disks, hard disks, removable cartridges, orflash drives. In one example, storage medium 4221 may be configured toinclude operating system 4223, application program 4225 such as a webbrowser application, a widget or gadget engine or another application,and data file 4227. Storage medium 4221 may store, for use by UE 4200,any of a variety of various operating systems or combinations ofoperating systems.

Storage medium 4221 may be configured to include a number of physicaldrive units, such as redundant array of independent disks (RAID), floppydisk drive, flash memory, USB flash drive, external hard disk drive,thumb drive, pen drive, key drive, high-density digital versatile disc(HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray opticaldisc drive, holographic digital data storage (HDDS) optical disc drive,external mini-dual in-line memory module (DIMM), synchronous dynamicrandom access memory (SDRAM), external micro-DIMM SDRAM, smartcardmemory such as a subscriber identity module or a removable user identity(SIM/RUIM) module, other memory, or any combination thereof. Storagemedium 4221 may allow UE 4200 to access computer-executableinstructions, application programs or the like, stored on transitory ornon-transitory memory media, to off-load data, or to upload data. Anarticle of manufacture, such as one utilizing a communication system maybe tangibly embodied in storage medium 4221, which may comprise a devicereadable medium.

In FIG. 22 , processing circuitry 4201 may be configured to communicatewith network 4243 b using communication subsystem 4231. Network 4243 aand network 4243 b may be the same network or networks or differentnetwork or networks. Communication subsystem 4231 may be configured toinclude one or more transceivers used to communicate with network 4243b. For example, communication subsystem 4231 may be configured toinclude one or more transceivers used to communicate with one or moreremote transceivers of another device capable of wireless communicationsuch as another WD, UE, or base station of a radio access network (RAN)according to one or more communication protocols, such as IEEE 802.42,CDMA, WCDMA, GSM, LTE, UTRAN, WiMax, or the like. Each transceiver mayinclude transmitter 4233 and/or receiver 4235 to implement transmitteror receiver functionality, respectively, appropriate to the RAN links(e.g., frequency allocations and the like). Further, transmitter 4233and receiver 4235 of each transceiver may share circuit components,software or firmware, or alternatively may be implemented separately.

In the illustrated embodiment, the communication functions ofcommunication subsystem 4231 may include data communication, voicecommunication, multimedia communication, short-range communications suchas Bluetooth, near-field communication, location-based communicationsuch as the use of the global positioning system (GPS) to determine alocation, another like communication function, or any combinationthereof. For example, communication subsystem 4231 may include cellularcommunication, Wi-Fi communication, Bluetooth communication, and GPScommunication. Network 4243 b may encompass wired and/or wirelessnetworks such as a local-area network (LAN), a wide-area network (WAN),a computer network, a wireless network, a telecommunications network,another like network or any combination thereof. For example, network4243 b may be a cellular network, a Wi-Fi network, and/or a near-fieldnetwork. Power source 4213 may be configured to provide alternatingcurrent (AC) or direct current (DC) power to components of UE 4200.

The features, benefits and/or functions described herein may beimplemented in one of the components of UE 4200 or partitioned acrossmultiple components of UE 4200. Further, the features, benefits, and/orfunctions described herein may be implemented in any combination ofhardware, software or firmware. In one example, communication subsystem4231 may be configured to include any of the components describedherein. Further, processing circuitry 4201 may be configured tocommunicate with any of such components over bus 4202. In anotherexample, any of such components may be represented by programinstructions stored in memory that when executed by processing circuitry4201 perform the corresponding functions described herein. In anotherexample, the functionality of any of such components may be partitionedbetween processing circuitry 4201 and communication subsystem 4231. Inanother example, the non-computationally intensive functions of any ofsuch components may be implemented in software or firmware and thecomputationally intensive functions may be implemented in hardware.

FIG. 23 illustrates a virtualization environment in accordance with someembodiments.

FIG. 23 is a schematic block diagram illustrating a virtualizationenvironment 4300 in which functions implemented by some embodiments maybe virtualized. In the present context, virtualizing means creatingvirtual versions of apparatuses or devices which may includevirtualizing hardware platforms, storage devices and networkingresources. As used herein, virtualization can be applied to a node(e.g., a virtualized base station or a virtualized radio access node) orto a device (e.g., a UE, a wireless device or any other type ofcommunication device) or components thereof and relates to animplementation in which at least a portion of the functionality isimplemented as one or more virtual components (e.g., via one or moreapplications, components, functions, virtual machines or containersexecuting on one or more physical processing nodes in one or morenetworks).

In some embodiments, some or all of the functions described herein maybe implemented as virtual components executed by one or more virtualmachines implemented in one or more virtual environments 4300 hosted byone or more of hardware nodes 4330. Further, in embodiments in which thevirtual node is not a radio access node or does not require radioconnectivity (e.g., a core network node), then the network node may beentirely virtualized.

The functions may be implemented by one or more applications 4320 (whichmay alternatively be called software instances, virtual appliances,network functions, virtual nodes, virtual network functions, etc.)operative to implement some of the features, functions, and/or benefitsof some of the embodiments disclosed herein. Applications 4320 are runin virtualization environment 4300 which provides hardware 4330comprising processing circuitry 4360 and memory 4390. Memory 4390contains instructions 4395 executable by processing circuitry 4360whereby application 4320 is operative to provide one or more of thefeatures, benefits, and/or functions disclosed herein.

Virtualization environment 4300, comprises general-purpose orspecial-purpose network hardware devices 4330 comprising a set of one ormore processors or processing circuitry 4360, which may be commercialoff-the-shelf (COTS) processors, dedicated Application SpecificIntegrated Circuits (ASICs), or any other type of processing circuitryincluding digital or analog hardware components or special purposeprocessors. Each hardware device may comprise memory 4390-1 which may benon-persistent memory for temporarily storing instructions 4395 orsoftware executed by processing circuitry 4360. Each hardware device maycomprise one or more network interface controllers (NICs) 4370, alsoknown as network interface cards, which include physical networkinterface 4380. Each hardware device may also include non-transitory,persistent, machine-readable storage media 4390-2 having stored thereinsoftware 4395 and/or instructions executable by processing circuitry4360. Software 4395 may include any type of software including softwarefor instantiating one or more virtualization layers 4350 (also referredto as hypervisors), software to execute virtual machines 4340 as well assoftware allowing it to execute functions, features and/or benefitsdescribed in relation with some embodiments described herein.

Virtual machines 4340, comprise virtual processing, virtual memory,virtual networking or interface and virtual storage, and may be run by acorresponding virtualization layer 4350 or hypervisor. Differentembodiments of the instance of virtual appliance 4320 may be implementedon one or more of virtual machines 4340, and the implementations may bemade in different ways.

During operation, processing circuitry 4360 executes software 4395 toinstantiate the hypervisor or virtualization layer 4350, which maysometimes be referred to as a virtual machine monitor (VMM).Virtualization layer 4350 may present a virtual operating platform thatappears like networking hardware to virtual machine 4340.

As shown in FIG. 23 , hardware 4330 may be a standalone network nodewith generic or specific components. Hardware 4330 may comprise antenna43225 and may implement some functions via virtualization.Alternatively, hardware 4330 may be part of a larger cluster of hardware(e.g. such as in a data center or customer premise equipment (CPE))where many hardware nodes work together and are managed via managementand orchestration (MANO) 43100, which, among others, oversees lifecyclemanagement of applications 4320.

Virtualization of the hardware is in some contexts referred to asnetwork function virtualization (NFV). NFV may be used to consolidatemany network equipment types onto industry standard high volume serverhardware, physical switches, and physical storage, which can be locatedin data centers, and customer premise equipment.

In the context of NFV, virtual machine 4340 may be a softwareimplementation of a physical machine that runs programs as if they wereexecuting on a physical, non-virtualized machine. Each of virtualmachines 4340, and that part of hardware 4330 that executes that virtualmachine, be it hardware dedicated to that virtual machine and/orhardware shared by that virtual machine with others of the virtualmachines 4340, forms a separate virtual network elements (VNE).

Still in the context of NFV, Virtual Network Function (VNF) isresponsible for handling specific network functions that run in one ormore virtual machines 4340 on top of hardware networking infrastructure4330 and corresponds to application 4320 in FIG. 23 .

In some embodiments, one or more radio units 43200 that each include oneor more transmitters 43220 and one or more receivers 43210 may becoupled to one or more antennas 43225. Radio units 43200 may communicatedirectly with hardware nodes 4330 via one or more appropriate networkinterfaces and may be used in combination with the virtual components toprovide a virtual node with radio capabilities, such as a radio accessnode or a base station.

In some embodiments, some signalling can be effected with the use ofcontrol system 43230 which may alternatively be used for communicationbetween the hardware nodes 4330 and radio units 43200.

FIG. 24 illustrates a telecommunication network connected via anintermediate network to a host computer in accordance with someembodiments.

With reference to FIG. 24 , in accordance with an embodiment, acommunication system includes telecommunication network 4410, such as a3GPP-type cellular network, which comprises access network 4411, such asa radio access network, and core network 4414. Access network 4411comprises a plurality of base stations 4412 a, 4412 b, 4412 c, such asNBs, eNBs, gNBs or other types of wireless access points, each defininga corresponding coverage area 4413 a, 4413 b, 4413 c. Each base station4412 a, 4412 b, 4412 c is connectable to core network 4414 over a wiredor wireless connection 4415. A first UE 4491 located in coverage area4413 c is configured to wirelessly connect to, or be paged by, thecorresponding base station 4412 c. A second UE 4492 in coverage area4413 a is wirelessly connectable to the corresponding base station 4412a. While a plurality of UEs 4491, 4492 are illustrated in this example,the disclosed embodiments are equally applicable to a situation where asole UE is in the coverage area or where a sole UE is connecting to thecorresponding base station 4412.

Telecommunication network 4410 is itself connected to host computer4430, which may be embodied in the hardware and/or software of astandalone server, a cloud-implemented server, a distributed server oras processing resources in a server farm. Host computer 4430 may beunder the ownership or control of a service provider, or may be operatedby the service provider or on behalf of the service provider.Connections 4421 and 4422 between telecommunication network 4410 andhost computer 4430 may extend directly from core network 4414 to hostcomputer 4430 or may go via an optional intermediate network 4420.Intermediate network 4420 may be one of, or a combination of more thanone of, a public, private or hosted network; intermediate network 4420,if any, may be a backbone network or the Internet; in particular,intermediate network 4420 may comprise two or more sub-networks (notshown).

The communication system of FIG. 24 as a whole enables connectivitybetween the connected UEs 4491, 4492 and host computer 4430. Theconnectivity may be described as an over-the-top (OTT) connection 4450.Host computer 4430 and the connected UEs 4491, 4492 are configured tocommunicate data and/or signaling via OTT connection 4450, using accessnetwork 4411, core network 4414, any intermediate network 4420 andpossible further infrastructure (not shown) as intermediaries. OTTconnection 4450 may be transparent in the sense that the participatingcommunication devices through which OTT connection 4450 passes areunaware of routing of uplink and downlink communications. For example,base station 4412 may not or need not be informed about the past routingof an incoming downlink communication with data originating from hostcomputer 4430 to be forwarded (e.g., handed over) to a connected UE4491. Similarly, base station 4412 need not be aware of the futurerouting of an outgoing uplink communication originating from the UE 4491towards the host computer 4430.

FIG. 25 illustrates a host computer communicating via a base stationwith a user equipment over a partially wireless connection in accordancewith some embodiments.

Example implementations, in accordance with an embodiment, of the UE,base station and host computer discussed in the preceding paragraphswill now be described with reference to FIG. 25 . In communicationsystem 4500, host computer 4510 comprises hardware 4515 includingcommunication interface 4516 configured to set up and maintain a wiredor wireless connection with an interface of a different communicationdevice of communication system 4500. Host computer 4510 furthercomprises processing circuitry 4518, which may have storage and/orprocessing capabilities. In particular, processing circuitry 4518 maycomprise one or more programmable processors, application-specificintegrated circuits, field programmable gate arrays or combinations ofthese (not shown) adapted to execute instructions. Host computer 4510further comprises software 4511, which is stored in or accessible byhost computer 4510 and executable by processing circuitry 4518. Software4511 includes host application 4512. Host application 4512 may beoperable to provide a service to a remote user, such as UE 4530connecting via OTT connection 4550 terminating at UE 4530 and hostcomputer 4510. In providing the service to the remote user, hostapplication 4512 may provide user data which is transmitted using OTTconnection 4550.

Communication system 4500 further includes base station 4520 provided ina telecommunication system and comprising hardware 4525 enabling it tocommunicate with host computer 4510 and with UE 4530. Hardware 4525 mayinclude communication interface 4526 for setting up and maintaining awired or wireless connection with an interface of a differentcommunication device of communication system 4500, as well as radiointerface 4527 for setting up and maintaining at least wirelessconnection 4570 with UE 4530 located in a coverage area (not shown inFIG. 45 ) served by base station 4520. Communication interface 4526 maybe configured to facilitate connection 4560 to host computer 4510.Connection 4560 may be direct or it may pass through a core network (notshown in FIG. 45 ) of the telecommunication system and/or through one ormore intermediate networks outside the telecommunication system. In theembodiment shown, hardware 4525 of base station 4520 further includesprocessing circuitry 4528, which may comprise one or more programmableprocessors, application-specific integrated circuits, field programmablegate arrays or combinations of these (not shown) adapted to executeinstructions. Base station 4520 further has software 4521 storedinternally or accessible via an external connection.

Communication system 4500 further includes UE 4530 already referred to.Its hardware 4535 may include radio interface 4537 configured to set upand maintain wireless connection 4570 with a base station serving acoverage area in which UE 4530 is currently located. Hardware 4535 of UE4530 further includes processing circuitry 4538, which may comprise oneor more programmable processors, application-specific integratedcircuits, field programmable gate arrays or combinations of these (notshown) adapted to execute instructions. UE 4530 further comprisessoftware 4531, which is stored in or accessible by UE 4530 andexecutable by processing circuitry 4538. Software 4531 includes clientapplication 4532. Client application 4532 may be operable to provide aservice to a human or non-human user via UE 4530, with the support ofhost computer 4510. In host computer 4510, an executing host application4512 may communicate with the executing client application 4532 via OTTconnection 4550 terminating at UE 4530 and host computer 4510. Inproviding the service to the user, client application 4532 may receiverequest data from host application 4512 and provide user data inresponse to the request data. OTT connection 4550 may transfer both therequest data and the user data. Client application 4532 may interactwith the user to generate the user data that it provides.

It is noted that host computer 4510, base station 4520 and UE 4530illustrated in FIG. 25 may be similar or identical to host computer4430, one of base stations 4412 a, 4412 b, 4412 c and one of UEs 4491,4492 of FIG. 24 , respectively. This is to say, the inner workings ofthese entities may be as shown in FIG. 25 and independently, thesurrounding network topology may be that of FIG. 24 .

In FIG. 25 , OTT connection 4550 has been drawn abstractly to illustratethe communication between host computer 4510 and UE 4530 via basestation 4520, without explicit reference to any intermediary devices andthe precise routing of messages via these devices. Networkinfrastructure may determine the routing, which it may be configured tohide from UE 4530 or from the service provider operating host computer4510, or both. While OTT connection 4550 is active, the networkinfrastructure may further take decisions by which it dynamicallychanges the routing (e.g., on the basis of load balancing considerationor reconfiguration of the network).

Wireless connection 4570 between UE 4530 and base station 4520 is inaccordance with the teachings of the embodiments described throughoutthis disclosure. One or more of the various embodiments may improve theperformance of OTT services provided to UE 4530 using OTT connection4550, in which wireless connection 4570 forms the last segment. Moreprecisely, the teachings of these embodiments may improve the randomaccess speed and/or reduce random access failure rates and therebyprovide benefits such as faster and/or more reliable random access.

A measurement procedure may be provided for the purpose of monitoringdata rate, latency and other factors on which the one or moreembodiments improve. There may further be an optional networkfunctionality for reconfiguring OTT connection 4550 between hostcomputer 4510 and UE 4530, in response to variations in the measurementresults. The measurement procedure and/or the network functionality forreconfiguring OTT connection 4550 may be implemented in software 4511and hardware 4515 of host computer 4510 or in software 4531 and hardware4535 of UE 4530, or both. In embodiments, sensors (not shown) may bedeployed in or in association with communication devices through whichOTT connection 4550 passes; the sensors may participate in themeasurement procedure by supplying values of the monitored quantitiesexemplified above, or supplying values of other physical quantities fromwhich software 4511, 4531 may compute or estimate the monitoredquantities. The reconfiguring of OTT connection 4550 may include messageformat, retransmission settings, preferred routing etc.; thereconfiguring need not affect base station 4520, and it may be unknownor imperceptible to base station 4520. Such procedures andfunctionalities may be known and practiced in the art. In certainembodiments, measurements may involve proprietary UE signalingfacilitating host computer 4510's measurements of throughput,propagation times, latency and the like. The measurements may beimplemented in that software 4511 and 4531 causes messages to betransmitted, in particular empty or ‘dummy’ messages, using OTTconnection 4550 while it monitors propagation times, errors etc.

FIG. 26 illustrates methods implemented in a communication systemincluding a host computer, a base station and a user equipment inaccordance with some embodiments

FIG. 26 is a flowchart illustrating a method implemented in acommunication system, in accordance with one embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIGS. 24 and 25 . Forsimplicity of the present disclosure, only drawing references to FIG. 26will be included in this section. In step 4610, the host computerprovides user data. In substep 4611 (which may be optional) of step4610, the host computer provides the user data by executing a hostapplication. In step 4620, the host computer initiates a transmissioncarrying the user data to the UE. In step 4630 (which may be optional),the base station transmits to the UE the user data which was carried inthe transmission that the host computer initiated, in accordance withthe teachings of the embodiments described throughout this disclosure.In step 4640 (which may also be optional), the UE executes a clientapplication associated with the host application executed by the hostcomputer.

FIG. 27 illustrates methods implemented in a communication systemincluding a host computer, a base station and a user equipment inaccordance with some embodiments.

FIG. 27 is a flowchart illustrating a method implemented in acommunication system, in accordance with one embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIGS. 24 and 25 . Forsimplicity of the present disclosure, only drawing references to FIG. 27will be included in this section. In step 4710 of the method, the hostcomputer provides user data. In an optional substep (not shown) the hostcomputer provides the user data by executing a host application. In step4720, the host computer initiates a transmission carrying the user datato the UE. The transmission may pass via the base station, in accordancewith the teachings of the embodiments described throughout thisdisclosure. In step 4730 (which may be optional), the UE receives theuser data carried in the transmission.

FIG. 28 illustrates methods implemented in a communication systemincluding a host computer, a base station and a user equipment inaccordance with some embodiments

FIG. 28 is a flowchart illustrating a method implemented in acommunication system, in accordance with one embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIGS. 24 and 25 . Forsimplicity of the present disclosure, only drawing references to FIG. 28will be included in this section. In step 4810 (which may be optional),the UE receives input data provided by the host computer. Additionallyor alternatively, in step 4820, the UE provides user data. In substep4821 (which may be optional) of step 4820, the UE provides the user databy executing a client application. In substep 4811 (which may beoptional) of step 4810, the UE executes a client application whichprovides the user data in reaction to the received input data providedby the host computer. In providing the user data, the executed clientapplication may further consider user input received from the user.Regardless of the specific manner in which the user data was provided,the UE initiates, in substep 4830 (which may be optional), transmissionof the user data to the host computer. In step 4840 of the method, thehost computer receives the user data transmitted from the UE, inaccordance with the teachings of the embodiments described throughoutthis disclosure.

FIG. 29 illustrates methods implemented in a communication systemincluding a host computer, a base station and a user equipment inaccordance with some embodiments

FIG. 29 is a flowchart illustrating a method implemented in acommunication system, in accordance with one embodiment. Thecommunication system includes a host computer, a base station and a UEwhich may be those described with reference to FIGS. 24 and 25 . Forsimplicity of the present disclosure, only drawing references to FIG. 29will be included in this section. In step 4910 (which may be optional),in accordance with the teachings of the embodiments described throughoutthis disclosure, the base station receives user data from the UE. Instep 4920 (which may be optional), the base station initiatestransmission of the received user data to the host computer. In step4930 (which may be optional), the host computer receives the user datacarried in the transmission initiated by the base station.

Any appropriate steps, methods, features, functions, or benefitsdisclosed herein may be performed through one or more functional unitsor modules of one or more virtual apparatuses. Each virtual apparatusmay comprise a number of these functional units. These functional unitsmay be implemented via processing circuitry, which may include one ormore microprocessor or microcontrollers, as well as other digitalhardware, which may include digital signal processors (DSPs),special-purpose digital logic, and the like. The processing circuitrymay be configured to execute program code stored in memory, which mayinclude one or several types of memory such as read-only memory (ROM),random-access memory (RAM), cache memory, flash memory devices, opticalstorage devices, etc. Program code stored in memory includes programinstructions for executing one or more telecommunications and/or datacommunications protocols as well as instructions for carrying out one ormore of the techniques described herein. In some implementations, theprocessing circuitry may be used to cause the respective functional unitto perform corresponding functions according one or more embodiments ofthe present disclosure.

The term unit may have conventional meaning in the field of electronics,electrical devices and/or electronic devices and may include, forexample, electrical and/or electronic circuitry, devices, modules,processors, memories, logic solid state and/or discrete devices,computer programs or instructions for carrying out respective tasks,procedures, computations, outputs, and/or displaying functions, and soon, as such as those that are described herein.

Abbreviations

At least some of the following abbreviations may be used in thisdisclosure. If there is an inconsistency between abbreviations,preference should be given to how it is used above. If listed multipletimes below, the first listing should be preferred over any subsequentlisting(s).

-   -   1×RTT CDMA2000 1×Radio Transmission Technology    -   3GPP 3rd Generation Partnership Project    -   5G 5th Generation    -   ABS Almost Blank Subframe    -   ARQ Automatic Repeat Request    -   AWGN Additive White Gaussian Noise    -   BCCH Broadcast Control Channel    -   BCH Broadcast Channel    -   CA Carrier Aggregation    -   CC Carrier Component    -   CCCH SDU Common Control Channel SDU    -   CDMA Code Division Multiplexing Access    -   CGI Cell Global Identifier    -   CIR Channel Impulse Response    -   CP Cyclic Prefix    -   CPICH Common Pilot Channel    -   CPICH Ec/No CPICH Received energy per chip divided by the power        density in the band    -   CQI Channel Quality information    -   C-RNTI Cell RNTI    -   CSI Channel State Information    -   DCCH Dedicated Control Channel    -   DL Downlink    -   DM Demodulation    -   DMRS Demodulation Reference Signal    -   DRX Discontinuous Reception    -   DTX Discontinuous Transmission    -   DTCH Dedicated Traffic Channel    -   DUT Device Under Test    -   E-CID Enhanced Cell-ID (positioning method)    -   E-SMLC Evolved-Serving Mobile Location Centre    -   ECGI Evolved CGI    -   eNB E-UTRAN NodeB    -   ePDCCH enhanced Physical Downlink Control Channel    -   E-SMLC evolved Serving Mobile Location Center    -   E-UTRA Evolved UTRA    -   E-UTRAN Evolved UTRAN    -   FDD Frequency Division Duplex    -   PPS For Further Study    -   GERAN GSM EDGE Radio Access Network    -   gNB Base station in NR    -   GNSS Global Navigation Satellite System    -   GSM Global System for Mobile communication    -   HARQ Hybrid Automatic Repeat Request    -   HO Handover    -   HSPA High Speed Packet Access    -   HRPD High Rate Packet Data    -   LOS Line of Sight    -   LPP LTE Positioning Protocol    -   LTE Long-Term Evolution    -   MAC Medium Access Control    -   MBMS Multimedia Broadcast Multicast Services    -   MBSFN Multimedia Broadcast multicast service Single Frequency        Network    -   MBSFN ABS MBSFN Almost Blank Subframe    -   MDT Minimization of Drive Tests    -   MIB Master Information Block    -   MME Mobility Management Entity    -   MSC Mobile Switching Center    -   NPDCCH Narrowband Physical Downlink Control Channel    -   NR New Radio    -   OCNG OFDMA Channel Noise Generator    -   OFDM Orthogonal Frequency Division Multiplexing    -   OFDMA Orthogonal Frequency Division Multiple Access    -   OSS Operations Support System    -   OTDOA Observed Time Difference of Arrival    -   O&M Operation and Maintenance    -   PBCH Physical Broadcast Channel    -   P-CCPCH Primary Common Control Physical Channel    -   PCell Primary Cell    -   PCFICH Physical Control Format Indicator Channel    -   PDCCH Physical Downlink Control Channel    -   PDP Profile Delay Profile    -   PDSCH Physical Downlink Shared Channel    -   PGW Packet Gateway    -   PHICH Physical Hybrid-ARQ Indicator Channel    -   PLMN Public Land Mobile Network    -   PMI Precoder Matrix Indicator    -   PRACH Physical Random Access Channel    -   PRS Positioning Reference Signal    -   PSS Primary Synchronization Signal    -   PUCCH Physical Uplink Control Channel    -   PUSCH Physical Uplink Shared Channel    -   RACH Random Access Channel    -   QAM Quadrature Amplitude Modulation    -   RAN Radio Access Network    -   RAT Radio Access Technology    -   RLM Radio Link Management    -   RNC Radio Network Controller    -   RNTI Radio Network Temporary Identifier    -   RRC Radio Resource Control    -   RRM Radio Resource Management    -   RS Reference Signal    -   RSCP Received Signal Code Power    -   RSRP Reference Symbol Received Power OR Reference Signal        Received Power    -   RSRQ Reference Signal Received Quality OR Reference Symbol        Received Quality    -   RSSI Received Signal Strength Indicator    -   RSTD Reference Signal Time Difference    -   SCH Synchronization Channel    -   SCell Secondary Cell    -   SDU Service Data Unit    -   SFN System Frame Number    -   SGW Serving Gateway    -   SI System Information    -   SIB System Information Block    -   SNR Signal to Noise Ratio    -   SON Self Optimized Network    -   SS Synchronization Signal    -   SSS Secondary Synchronization Signal    -   TDD Time Division Duplex    -   TDOA Time Difference of Arrival    -   TOA Time of Arrival    -   TSS Tertiary Synchronization Signal    -   TTI Transmission Time Interval    -   UE User Equipment    -   UL Uplink    -   UMTS Universal Mobile Telecommunication System    -   USIM Universal Subscriber Identity Module    -   UTDOA Uplink Time Difference of Arrival    -   UTRA Universal Terrestrial Radio Access    -   UTRAN Universal Terrestrial Radio Access Network    -   WCDMA Wide CDMA    -   WLAN Wide Local Area Network

Further definitions and embodiments are discussed below.

In the above-description of various embodiments of present inventiveconcepts, it is to be understood that the terminology used herein is forthe purpose of describing particular embodiments only and is notintended to be limiting of present inventive concepts. Unless otherwisedefined, all terms (including technical and scientific terms) usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which present inventive concepts belong. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of this specification andthe relevant art and will not be interpreted in an idealized or overlyformal sense unless expressly so defined herein.

When an element is referred to as being “connected”, “coupled”,“responsive”, or variants thereof to another element, it can be directlyconnected, coupled, or responsive to the other element or interveningelements may be present. In contrast, when an element is referred to asbeing “directly connected”, “directly coupled”, “directly responsive”,or variants thereof to another element, there are no interveningelements present. Like numbers refer to like elements throughout.Furthermore, “coupled”, “connected”, “responsive”, or variants thereofas used herein may include wirelessly coupled, connected, or responsive.As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. Well-known functions or constructions may not be described indetail for brevity and/or clarity. The term “and/or” (abbreviated “/”)includes any and all combinations of one or more of the associatedlisted items.

It will be understood that although the terms first, second, third, etc.may be used herein to describe various elements/operations, theseelements/operations should not be limited by these terms. These termsare only used to distinguish one element/operation from anotherelement/operation. Thus a first element/operation in some embodimentscould be termed a second element/operation in other embodiments withoutdeparting from the teachings of present inventive concepts. The samereference numerals or the same reference designators denote the same orsimilar elements throughout the specification.

As used herein, the terms “comprise”, “comprising”, “comprises”,“include”, “including”, “includes”, “have”, “has”, “having”, or variantsthereof are open-ended, and include one or more stated features,integers, elements, steps, components or functions but does not precludethe presence or addition of one or more other features, integers,elements, steps, components, functions or groups thereof. Furthermore,as used herein, the common abbreviation “e.g.”, which derives from theLatin phrase “exempli gratia,” may be used to introduce or specify ageneral example or examples of a previously mentioned item, and is notintended to be limiting of such item. The common abbreviation “i.e.”,which derives from the Latin phrase “id est,” may be used to specify aparticular item from a more general recitation.

Example embodiments are described herein with reference to blockdiagrams and/or flowchart illustrations of computer-implemented methods,apparatus (systems and/or devices) and/or computer program products. Itis understood that a block of the block diagrams and/or flowchartillustrations, and combinations of blocks in the block diagrams and/orflowchart illustrations, can be implemented by computer programinstructions that are performed by one or more computer circuits. Thesecomputer program instructions may be provided to a processor circuit ofa general purpose computer circuit, special purpose computer circuit,and/or other programmable data processing circuit to produce a machine,such that the instructions, which execute via the processor of thecomputer and/or other programmable data processing apparatus, transformand control transistors, values stored in memory locations, and otherhardware components within such circuitry to implement thefunctions/acts specified in the block diagrams and/or flowchart block orblocks, and thereby create means (functionality) and/or structure forimplementing the functions/acts specified in the block diagrams and/orflowchart block(s).

These computer program instructions may also be stored in a tangiblecomputer-readable medium that can direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer-readablemedium produce an article of manufacture including instructions whichimplement the functions/acts specified in the block diagrams and/orflowchart block or blocks. Accordingly, embodiments of present inventiveconcepts may be embodied in hardware and/or in software (includingfirmware, resident software, micro-code, etc.) that runs on a processorsuch as a digital signal processor, which may collectively be referredto as “circuitry,” “a module” or variants thereof.

It should also be noted that in some alternate implementations, thefunctions/acts noted in the blocks may occur out of the order noted inthe flowcharts. For example, two blocks shown in succession may in factbe executed substantially concurrently or the blocks may sometimes beexecuted in the reverse order, depending upon the functionality/actsinvolved. Moreover, the functionality of a given block of the flowchartsand/or block diagrams may be separated into multiple blocks and/or thefunctionality of two or more blocks of the flowcharts and/or blockdiagrams may be at least partially integrated. Finally, other blocks maybe added/inserted between the blocks that are illustrated, and/orblocks/operations may be omitted without departing from the scope ofinventive concepts. Moreover, although some of the diagrams includearrows on communication paths to show a primary direction ofcommunication, it is to be understood that communication may occur inthe opposite direction to the depicted arrows.

Many variations and modifications can be made to the embodiments withoutsubstantially departing from the principles of the present inventiveconcepts. All such variations and modifications are intended to beincluded herein within the scope of present inventive concepts.Accordingly, the above disclosed subject matter is to be consideredillustrative, and not restrictive, and the examples of embodiments areintended to cover all such modifications, enhancements, and otherembodiments, which fall within the spirit and scope of present inventiveconcepts. Thus, to the maximum extent allowed by law, the scope ofpresent inventive concepts are to be determined by the broadestpermissible interpretation of the present disclosure including theexamples of embodiments and their equivalents, and shall not berestricted or limited by the foregoing detailed description.

Appendix 1 is part of this specification.

APPENDIX 1 3GPP TSG-RAN WG1 Meeting #99 Tdoc R1-19xxxxx Reno, USA, Nov.18^(th)-22^(nd), 2019 Agenda Item: 7.2.8.2 Source: Ericsson Title:Finalizing issues for mTRP Document for: Discussion, Decision

1 Introduction

This contribution discusses remaining issues for multi-TRP/multi-panel(mTRP) operation in NR Rel-16.

2 Remaining Issues for Single Pdcch Based Multi-Trp Scheduling 2.1 LTECRS Rate Matching

-   Proposal 1 For single PDCCH case, if two overlapping LTE CRS    patterns are configured, the UE shall rate match PDSCH around both    LTE CRS, for all received layers.

2.1 Default TCI State

An open issue is related to K1 value and which TCI state to apply. WhenK1 is smaller than the threshold, what is the default TCI state? Fromour understanding, the threshold was introduced to allow a UE in FR2 topossibly use a known wide Rx beam for PDSCH reception if the UE doesn'thave enough time to switch to a beam indicated by the TCI. In case ofMulti-TRP, a UE would be indicated with 2 TCI states, corresponding to 2Rx beams. The main use case of indicating a K1 value below the thresholdwould be for fast PDSCH scheduling over the PDCCH beam such that the UEcan receive it without beam switching. Therefore, we have the followingproposal:

-   Proposal 2 When 2 TCI states are indicated in DCI and the K1 value    in the same DCI is below the threshold, the default TCI states are    the TCI states indicated in the DCI or TCIs associated to 2    CORESETs.

2.2 Combination of 2 TCI States and 1 or 3 CDM Groups

A remaining open issue is how the UE shall handle the case of 2indicated TCI states and 3 CDM groups. Our preferred resolution is thefollowing:

-   Proposal 3 If a TCI codepoint indicates two TCI states and indicated    DMRS ports are from single CDM group, and if repetition scheme is    not enabled (i.e. URLLC based scheme not enabled), then the UE    applies the first TCI state and ignores the second TCI state in the    codepoint.

And in the case of 3 CDM groups:

-   Proposal 4 If a TCI codepoint indicates two TCI states and indicated    DMRS ports are from three CDM groups, then the UE associates the    first TCI state to the first CDM group (λ=0) and the second TCI    states to the second and third CDM group (λ=1, 2).

2.3 PT-RS Port to DM-RS Port Association for Rank 5 and 6

In Rel.15 downlink PT-RS procedures, in case of two CW is scheduled tobe transmitted (rank 5 or 6), the PT-RS port is associated to the DM-RSport that belongs to the CW with the highest MCS. This increases theprobability that the SNR for the layer that PT-RS is associated with hasa high SNR and as evaluations have shown during Rel.15, this improvesphase tracking performance and throughput.

In the previous meeting, it was agreed for the case of two PT-RS ports,the first/second PTRS port is associated with the lowest indexed DMRSport within the DMRS ports corresponding to the first/second indicatedTCI state, respectively. However, this agreement implies that for 2 CWtransmission, the PT-RS ports may in some cases be mapped to the layerwith the worst SNR.

Therefore, we propose the following for rank 5 and 6 case:

-   Proposal 5 If a UE is scheduled with two codewords and two PTRS    ports is configured for single-PDCCH based multi-TRP/Panel    transmission at least for eMBB and URLLC scheme 1a, and if two TCI    states are indicated by one TCI code point, and for each TCI state    -   if the TCI state is associated to two MCSs (i.e. the TCI state        is associated with two code words) then the first PTRS port is        associated with the lowest indexed DMRS port assigned for the        codeword with the higher MCS within the DMRS ports corresponding        to the TCI state, and    -   if the MCS indices of the two codewords are the same, then the        first/second PTRS port is associated with the lowest indexed        DMRS port within the DMRS ports corresponding to the        first/second indicated TCI state

We provide an example on how this proposal affects the association rule:For Type 1 DMRS, ports 0, 1, 4, 5 belong to first CDM group (first TCIstate) and ports 2, 3, 6, 7 belong to second CDM group (second TCIstate). Assume rank 5 scheduling where ports 0-4 are used, thenaccording to CW2L mapping, CW0 use port 0, 1 and CW1 use port 2, 3, 4.This leads to the following cases:

-   -   If MCS is higher for CW0 compared to CW1, then port 0 and port 2        are associated with PT-RS for the 1^(st) TCI state and 2^(nd)        TCI state, respectively.    -   If MCS is higher for CW1 compared to CW0, then port 4 and port 2        are associated with PT-RS for the 1^(st) TCI state and 2^(nd)        TCI state, respectively.    -   If MCS is same for CW1 and CW0, then port 0 and port 2 are        associated with PT-RS for the 1^(st) TCI state and 2^(nd) TCI        state, respectively.

2.4 the Case of Single CDM Group, 2 TCI States and 2 PT-RS Ports

Furthermore, we propose the following fallback in case of 2 PT-RS ports,2 TCI states are configured but a single CDM group is used for thePDSCH.

-   Proposal 6 If a TCI codepoint indicates two TCI states and indicated    DMRS ports are from single CDM group, and if two PT-RS ports are    enabled, then a single PT-RS port is transmitted.

3 Reliability/Robustness Specific Extensions for PDSCH 3.1 RemainingIssues for FDM Schemes 3.1.1 on the Issue of Two PTRS Ports for Scheme2A/2B

In Scheme 2a and 2b, each PRG is utilized for transmission by one of thetwo TRP only. Also, the DM-RS ports are from one CDM group onlyaccording to agreement with a comb-based frequency allocationtransmission, divided into odd and even PRGs (except in the case ofwideband PRG, in which case two continuous chunks or RBs are used perTRP). The same DM-RS port number(s) is used in the odd and even PRGs,hence there is no need to configure two PT-RS ports in scheme 2a and 2b.

-   Proposal 7 In Scheme 2a and 2b, a single PT-RS port is used. If two    PT-RS ports have been configured (in case dynamic switching between    schemes is supported), then only the PT-RS port associated with the    lowest index DM-RS port is transmitted.

The network may transmit the PT-RS port from each of the two TRPsrespectively. It may in some cases be so that phase noise contributionscome also from the transmitter side, i.e. gNB. This is particularly thecase if lower complexity gNBs are used, which doesn't have the samelocal oscillator stability as advanced macro gNBs. Hence, the UE may notjointly use PT-RS transmissions from PRGs that are transmitted fromdifferent TRPs, as they may have very different phase noisecharacteristics. Hence, we propose:

-   Proposal 8 In scheme 2a, the UE shall not assume that it can use the    PT-RS transmissions from PDSCH resources associated with different    TCI states in a joint manner, when using PT-RS for tracking the    phase. Hence, phase tracking needs to be estimated for each of the    two groups of PDSCH resources separately.

For Scheme 2b on the other hand, the procedure is simpler, as there aretwo CW transmitted, and thus two PDSCHs transmitted. A simple rule isthen the following:

-   Proposal 9 In scheme 2b, the PT-RS resource element mapping is    established for each of the two PDSCHs independently (i.e. to the    scheduled resources of the PDSCH). The UE shall not use PT-RS of one    PDSCH as the PT-RS for the other PDSCH.

Moreover, in scheme 2b, the actual number of RB used for transmissionfrom one TRP, i.e. per PDSCH, is roughly 50% of the total number ofscheduled RB since the resource allocation indicates the total resourcesused for both PDSCH. Hence, to correctly assign the frequency densityK_(PT-RS) of the PT-RS for each PDSCH, only 50% of the total scheduledbandwidth should be assumed per PDSCH. Hence,

-   Proposal 10 In scheme 2b, the value used for the bandwidth N_(RB)    when determining K_(PT-RS) from Table 5.1.6.3-2 in TS 38.214 is    ceil(X/2) where X is the total number of scheduled resource blocks    in the scheme 2b resource allocation.

3.1.2 RV Sequence for Scheme 2B

For Scheme 2b, agreement last meeting was:

Agreement

For single-DCI based M-TRP URLLC scheme 2b

-   -   For a RV sequence to be applied to RBs associated with two TCI        states sequentially,        -   RV_(id) indicated by the DCI is used to select one out of            four RV sequence candidates, whereas sequences are            predefined in spec (FFS exact sequences)

Based on simulation results provided in the previous meetings, e.g.,[6], it seems that at least (RV1,RV2)=(0,2) and (0,0) should besupported. (0,0) can be used in case of blocking while (0,2) can be usedwhen there is no blocking. This is because RV0 is self-decodable whileRV2 isn't. Thus, when one of the TRPs has the risk of being completelyblocked, it is better to transmit RV0 from both TRPs, so that at aself-decodable RV can be received. However, when the TRPs areexperiencing fading dips rather than blocking, it is better to transmitdifferent RVs to achieve incremental redundancy rather than chasecombining and (RV1,RV2)=(0,2) was shown to be the best combination.

Additionally, (2,2) and (1,3) may be included to support retransmission.For example, (2,2) may be used for retransmission when (0,0) was used inthe initial transmission to have (0,2) for each TRP in case one TRP isblocked. Similarly, (1,3) may be used for retransmission when (0,2) wasused in the initial transmission to have a combined RV sequence of (0,2, 3, 1) over two transmissions to maximize soft combining gain. Theresulted 4 RV sequences are shown in Table 1.

-   Proposal 11 For Scheme 2b, use the 4 RV sequences listed in Table 1.

TABLE 1 An example of RV configuration for Scheme 2b RV field in DCI RV1RV2 0 0 0 1 2 2 2 0 2 3 1 3

3.2 Remaining Issues for TDM Schemes 3.2.1 Repetition Indication forScheme 3

In RAN1 #98bis, the following was agreed for scheme 3.

-   -   Agreement    -   For single-DCI based M-TRP URLLC scheme 3, the starting symbol        of the second transmission occasion has K symbol offset relative        to the last symbol of the first transmission occasion, whereas        the value of K can be optionally configured by RRC. If not        configured, K=0.        -   The starting symbol and length of the first transmission            occasion is indicated by SLIV.        -   The length of the second transmission occasion is the same            with the first transmission occasion.        -   Exact candidate value of K can be decided in RAN1 #99        -   FFS: Any restrictions on the possible value pairs for K and            SLIV

In NR Rel-15, the starting symbol (S) and length (L) are jointly encodedas specified in clause 5.1.2.1 of TS 38.214 such that the time domainresource allocation does not cross the slot boundary. This means thereis a constraint 0<L≤14−S that must be met in NR Rel-15.

As already agreed in RAN1 #98bis, for scheme 3, the number oftransmission occasions is two when a codepoint of the TCI fieldindicates two TCI states. Hence, the constraint related to SLIV shouldbe modified taking into account the higher layer configured value of K.An appropriate constraint for the case when there is two transmissionoccasions is 0<2L≤14−S−K. This constraint ensures that the time domainresource allocation for the two transmission occasions does not crossthe slot boundary.

Furthermore, in the email discussion [98b-NR-22] related to the Rel-16NR eURLLC work item, the following agreement was made:

-   -   Agreement    -   For time domain resource allocation indication for PDSCH for        Rel-16 URLLC in new DCI format, using the starting symbol of the        PDCCH monitoring occasion in which the DL assignment is detected        as the reference of the SLIV is supported.        -   A RRC parameter is used to enable the utilization of the new            reference        -   When the RRC parameter enables the utilization of the new            reference, the new reference is applied for TDRA entries            with K0=0        -   FFS: Other entries with K0>0 can also be included in the            same TDRA table        -   For other entries (if any) in the same TDRA table, the            reference is slot boundary as in Rel-15.

In NR Rel-15, the starting symbol S is relative to the start of the slot(i.e., reference point is the start of the slot). However, according tothe above eURLLC agreement, the starting symbol S is relative to thestarting symbol of the PDCCH monitoring occasion in which the DLassignment is detected. Furthermore, as agreed above, the use of thisnew reference point is enabled/disabled by a new RRC parameter. Itshould be noted that when the use of the new reference point is enabled,the restrictions related to SLIV and K will be impacted. An appropriateconstraint for this case when there is two transmission occasions is0<2L≤14−S−S₀−K where S₀ denotes the starting symbol of the PDCCHmonitoring occasion in which the DL assignment is detected.

-   Proposal 12 With regards to restrictions on the possible value pairs    for K and SLIV for Scheme 3, the following restrictions apply, and    if the UE receives K and SLIV values in the scheduling DCI that do    not satisfy the conditions below, then the UE can assume that only    the first repetition in the slot is transmitted:    -   If using the starting symbol of the PDCCH monitoring occasion in        which the DL assignment is detected as the reference point for        starting symbol S is not enabled, then the restriction        0<2L≤14−S−K applies.    -   If using the starting symbol of the PDCCH monitoring occasion in        which the DL assignment is detected as the reference point for        starting symbol S is enabled, then the restriction        0<2L≤14−S−S₀−K applies wherein S₀ is the starting symbol of the        PDCCH monitoring occasion in which the DL assignment is        detected.

One of the reasons for introducing a configurable symbol offset K is toallow transmission of scheme 3 in a slot containing both DL and ULsymbols. Particularly, the use case for having a non-zero K value is toallow the case where there are UL symbols (and flexible symbols) inbetween the DL symbols allocated for the first transmission occasion andthe DL symbols allocated for the second transmission occasion.Considering Table 11.1.1-1 of TS 38.213, slot formats 46, 47, 49, 50,53, and 54 offer the possibility of 1^(st) transmission occasion in aset of DL symbols and the 2^(nd) transmission occasion in another set ofDL symbol wherein the two sets of DL symbols are separated byUL/flexible symbols.

Another motivation is to avoid collisions between PDSCH DMRS andreserved resources such as LTE CRS. FIG. 19 shows an illustration ofdifferent K values suitable for different slot formats. As shown in thefigure, K values in the range from 0 to 6 are useful. Hence, we proposethe following:

-   Proposal 13 Support a value range from 0 to 6 for the configurable    symbol offset K.

It should be noted that a single configured value of K is not suitablefor different slot formats particularly in the case when slot format isdynamically indicated. For instance, a K value of 6 which is suitablefor slot format 55 in FIG. 19 is not suitable for slot format 46.Furthermore, the same value of K is not suitable even within the sameslot format when different L values are used for scheme 3.

FIG. 20 shows a second illustration when different K values are neededwhen different L values are used within the same slot format. In the toppart of this figure, scheme 3 is used with L=4 which requires a K valueof 2. In the bottom part of the figure, scheme 3 is used with L=2 whichrequires a K value of 0. Hence, to maintain the scheduling flexibility,different values of K should allow to be dependent on the SLIV. SinceSLIV is indicated as part of PDSCH-TimeDomainResourceAllocation, wepropose to also indicate the K value as part ofPDSCH-TimeDomainResourceAllocation.

-   Proposal 14 In NR Rel-16, the symbol offset K for multi-TRP scheme 3    is configured as part of PDSCH-TimeDomainResourceAllocation.

3.2.2 Repetition Indication for Scheme 4

In RAN1 #98bis, the following was agreed.

-   -   Agreement    -   For single-DCI based M-TRP URLLC schemes, the number of        transmission occasions is indicated by following:        -   For scheme 3, the number of transmission occasions is            implicitly determined by the number of TCI states indicated            by a code point whereas one TCI state means one transmission            occasion and two states means two transmission occasions.    -   For scheme 4, TDRA indication is enhanced to additionally        indicate the number of PDSCH transmission occasions by using        PDSCH-TimeDomainResourceAllocation field.        -   The maximum number of repetition is FFS.

According to Clause 11.1 of TS 38.213, when a UE is scheduled by DCIformat 1-1 to receive PDSCH over multiple slots, and if a slot among themultiple slots contains at least one symbol from a set of symbols wherethe UE is scheduled to receive PDSCH is an uplink symbol, then the UEdoes not receive PDSCH in that slot. Hence, in multi-TRP scheme 4, someof the transmission occasions may not be received by the UE in someslots if at least one of the scheduled symbols for PDSCH happens to bean uplink symbol. These transmission occasions that are not received bythe UE are still counted as ‘one reception’ towards the indicated numberof transmission occasions. This may limit the reliability of scheme 4for certain TDD configurations.

In Rel-15, the maximum number of repetitions is 8. However, to ensurethe reliability of scheme 4 for various TDD configuration, it isdesirable to set the maximum number of repetitions to 16 in NR Rel-16.

-   Proposal 15 In NR Rel-16, the maximum number of repetitions for    scheme 4 is 16.

In NR Rel-16 eURLLC, the following agreement is made for PUSCH:

-   -   Agreements:    -   For the dynamic indication of the number of repetitions for        dynamic grant:        -   Jointly coded with SLIV in TDRA table, by adding an            additional column for the number of repetitions in the TDRA            table        -   The maximum TDRA table size is increased to 64        -   No other spec impact is expected

Similar to the above agreement, for scheme 4, we have agreed that thenumber of repetitions will be dynamically indicated by using thePDSCH-TimeDomainResourceAllocation field which also provides the SLIV.Hence, a similar level of scheduling flexibility is desired for PDSCH inthe case of scheme 4. Thus, in the case of scheme 4, the maximum TDRAtable size is 64.

-   Proposal 16 In NR Rel-16, the maximum TDRA table size given by    ‘maxNrofDL-Allocations’ in TS38.331 is 64.

3.2.3 RV Sequence for Scheme 3

Different RV sequences may be beneficial for different scenarios. Forexample, (0,0) may be used in case there is a high probability that oneTRP is blocked, while (0,2) may be used when blocking is a lowprobability. Up to 4 different RV sequences may be predefined and RVfield of DCI can be used to select one of the sequences, similar toRel-15. For Scheme 3 with only two repetitions, the same RV sequences inTable 1 for Scheme 2b may be used.

-   Proposal 17 Up to 4 RV sequences are predefined and the RV field in    DCI is re-used to select one of the sequences for Schemes 3 and the    same RV sequences as for Scheme 2b are used.

4 the Configuration of a Single TRP as a Special Case

For scheme 4, it has been agreed to dynamically

-   -   For scheme 4, TDRA indication is enhanced to additionally        indicate the number of PDSCH transmission occasions by using        PDSCH-TimeDomainResourceAllocation field.

5 On Dynamic Switching Between Schemes

Talk about switching between URLLC-Single TRP-Multi-TRP-EMBB

In RAN1 #98b, the following agreement was reached:

-   -   Agreement    -   For single-DCI based M-TRP URLLC scheme differentiation among        schemes 2a/2b/3, from the UE perspective:        -   A new RRC parameter is introduced to enable [one            scheme/multiple schemes] among 2a/2b/3.            -   FFS on details    -   Note: dynamic switching between schemes (including fallback) is        a separate discussion

If RRC is used to select one scheme among schemes 2a/2b/3, then there isno need for dynamic scheme selection principle among 2a/2b/3. If on theother hand, RRC is used to select either Scheme 2a/2b or Scheme 3, thendynamic selection between Schemes 2a and 2b would be needed.

From latency perspective, Schemes 2a/2b/3 are rather similar. For thesame amount of resource utilization per OFDM symbol, Scheme 3 wouldprovide more frequency diversity but double the DMRS overhead. In ourview, Scheme 3 is mainly beneficial for FR2 while Schemes 2a/2b aremainly beneficial for FR1.

Therefore, having RRC configuration of either Schemes 2a/2b or Scheme 3should be sufficient. Then, comparing Schemes 2a and 2b, it is noticedthey are very similar in performance when the code rate is low such thatsystematic bits are transmitted from each TRP. At high code rate, Scheme2a is slightly better when there is no deep fading or presence ofchannel blocking, otherwise, Scheme 2b is better. Given that Scheme 2balso needs additional UE capability signaling, RRC signaling issufficient in practice. Thus, this leads us to the following proposal:

-   Proposal 18 Either of Scheme 2a, 2b or 3 is semi-statically enabled    by RRC. No dynamic switching between these three different schemes    is supported. Dynamic fallback to single TRP and/or single    repetition is supported.

6 Remaining Issues for Multi-DCI Based Multi-TRP 6.1 Remaining IssuesRelated to RRC Signalling

From email discussion

6.2 Remaining Issues Related to PUCCH

From last meeting, we have this agreement with two options fordown-selection in the Multi-TRP agenda:

Agreement

With regarding to PUCCH resource group for M-DCI NCJT transmission,select one of following options in RAN1 #98bis

-   -   Option 1: Support configuring explicit PUCCH resource grouping        over resource or resource sets    -   Option 2: Support implicit PUCCH resource grouping up to NW        implementation whereas PUCCH may or may not be overlapped.

Furthermore, in RAN1 #97, the following working assumption was reachedin the Multi-Beam agenda:

Working Assumption

For the supported feature of simultaneous update/indication of a singlespatial relation per group of PUCCH by using one MAC CE, the followingconfiguration options for the group are supported:

-   -   At least up to two groups per BWP        -   FFS: Details on configuring the groups including whether to            use implicit method or explicit method            -   For example, each corresponding to different TRP/panel,                at least for multi-TRP/panel case            -   Another example, each corresponding to different active                spatial relation at least for single TRP case        -   If there is no consensus to support more than two groups,            only up to two groups will be supported in Rel-16

Currently, whether to introduce explicit PUCCH resource groups or not isbeing discussed in parallel in both the Multi-TRP and the Multi-Beamagendas. From our perspective, there may be a potential for conflictingagreements if such parallel discussions continue in RAN1 #98bis. Giventhat there is a working assumption in the Multi-Beam agenda, ourpreference is to discuss whether or not to introduce explicit PUCCHresource groups in the Multi-Beam agenda.

-   Observation 1 Whether to introduce explicit PUCCH resource groups or    not is currently being discussed parallelly in both the Multi-TRP    and the Multi-Beam agendas, and if such discussions continue, may    result in conflicting agreements.-   Proposal 19 Whether or not to introduce explicit PUCCH resource    groups or not should be decided in the Multi-beam agenda.

There is a remaining FFS related PUCCH resource groups given below whichwas already supposed to be concluded in RAN1 #98

-   -   FFS whether/how to associate PUCCH resource groups and        configured higher layer signaling indices of CORESETs (to be        concluded in RAN1 98)

In the multi-DCI based multi-TRP case, a scheduler corresponding to eachTRP will indicate to the UE which PUCCH resource to use for HARQACK/NACK feedback via the PUCCH resource indicator field in thescheduling DCI. Hence, the association between PUCCH resource group (ifagreed) and configured higher layer signaling index in CORESET isalready implicit, and we do not see the need to explicitly associatePUCCH resource groups and configured higher layer signaling indices ofCORESET. In fact, we fail to see what benefit such explicit associationwould bring.

-   Proposal 20 In NR Rel-16, explicit association between PUCCH    resource groups (if agreed in MB agenda) and higher layer signaling    indices of CORESETs is not supported.

6.3 Remaining Issues Related to Dynamic HARQ-ACK Codebooks

From last meeting we have this agreement with two alternatives fordown-selection for joint HARQ A/N feedback with multi-DCI:

Agreement

For joint dynamic HARQ-ACK codebook among M-TRP, select one fromfollowing alternatives in RAN1 #98bis

-   -   Alt 1: counter DAI is jointly counted across two TRPs (i.e.        different higher layer index configured per CORESET (if        configured)), and total DAI should count total number of DCIs in        a PDCCH monitoring occasion across CCs and TRPs.    -   Alt 2: counter DAI is counted per TRP, and total DAI should        count total number of DCIs in a PDCCH monitoring occasion across        CCs for each TRP. HARQ-ACK information bits are then        concatenated by the increasing order of TRPs (i.e. different        higher layer index configured per CORESET (if configured)).

The use case of joint HARQ ACK feedback is, in our view, mainly forideal backhaul with a single scheduler so that the HARQ A/N can be sentto a single TRP. Since the scheduling is done by a single scheduler, itmakes sense to count the DCIs jointly across two TRPs for both counterDAI and total DAI. This would also ease UE processing as it only needsto deal with a single set of counters and minimal change is requiredfrom Rel-15 procedure. Therefore, Alt 1 is preferred.

-   Proposal 21 Alt 1 is supported for joint HARQ ACK codebook with    multi-DCI.

For separate HARQ A/N feedback with multi-DCI based multi-TRPtransmission, we have the following agreement from last RAN1 meeting:

Agreement

For multi-DCI based multi-TRP transmission with separate ACK/NACKfeedback

-   -   UE is allowed to transmit two TDMed long PUCCHs within a slot    -   UE is allowed to transmit TDMed short PUCCH and long PUCCH        within a slot    -   UE is allowed to transmit TDMed short PUCCH and short PUCCH        within a slot FFS whether/how to use PRI indication with the        granularity of sub-slot for eMBB with M-TRP

In our understanding, the sub-slot based PUCCH resource allocationdiscussed in eURLLC session is mainly related to the granularity of K1.When a UL sub-slot is indicated, the PUCCH resource indicator (PRI)field in DCI would point to a PUCCH resource within the sub-slot.Therefore, the FFS item is not an issue in our view. For sub-slot basedPUCCH resource allocation and K1, we can reuse the mechanism that hasbeen agreed in eURLLC.

6.4 Remaining Issues Related to PDSCH Rate Matching

From last meeting we have this agreement

Agreement

For multi-DCI based multi-TRP/panel transmission, the UE shall ratematch around:

-   -   Configured CRS patterns which optionally associated with a        higher layer signaling index per CORESET (if configured) and are        applied to the PDSCH scheduled with a DCI detected on a CORESET        with the same higher layer index.        -   This is a UE optional feature with separate UE capability            signalling        -   If UE does not support this feature, the default UE            behaviour is the following:            -   For multi-DCI based multi-TRP/panel transmission, the UE                shall rate match PDSCH around configured CRS patterns                from multiple TRPs                FFS: Whether/How to handle DMRS shifting if CRS patterns                are configured.

To simplify the operation, if LTE CRS pattern is configured in any ofthe TRPs, the DMRS is shifted according to Rel.15 procedure for bothTRPs. Hence

-   Proposal 22 For multi-DCI based multi-TRP/panel transmission, if at    least one LTE CRS patterns is configured, then PDSCH DM-RS is    shifted according to Rel.15 procedure when DM-RS symbol collides    with LTE CRS symbol and the shift is always applied for both    received PDSCH.

6.4.1 Overlapping DMRS and PDSCH

For DMRS, different TCI states (i.e., TRPs) use different CDM groups.Hence, it is reasonable to also add the condition that PDSCH from oneTRP is not simultaneously overlapping with DMRS transmitted from anotherTRP. Whether to map PDSCH to REs not used for DMRS is controlled byselecting the corresponding row in the antenna port indication table.Hence, we propose:

-   Proposal 23 A UE receiving downlink NC-JT scheduling assignments of    two PDSCHs can ignore both scheduling assignments in case one of the    scheduled PDSCH is mapped to REs used for DMRS to the other    scheduled PDSCH to the same UE

6.5 Remaining Issues Related to DCI Format 1_0

In RAN1 #96, the following agreement was made:

Agreement

For a UE supporting multiple-PDCCH based multi-TRP/panel transmissionand each PDCCH schedules one PDSCH, at least for eMBB with non-idealbackhaul, support following restrictions:

-   -   The UE may be scheduled with fully/partially/non-overlapped        PDSCHs at time and frequency domain by multiple PDCCHs with        following restrictions:        -   . . .        -   The UE is not expected to have more than one TCI index with            DMRS ports within the same CDM group for fully/partially            overlapped PDSCHs        -   . . .

In RAN1 #96, the following agreement was made:

Agreement

For a UE supporting multiple-PDCCH based multi-TRP/panel transmissionand each PDCCH schedules one PDSCH, at least for eMBB with non-idealbackhaul, support following restrictions:

-   -   The UE may be scheduled with fully/partially/non-overlapped        PDSCHs at time and frequency domain by multiple PDCCHs with        following restrictions:        -   . . .        -   The UE is not expected to have more than one TCI index with            DMRS ports within the same CDM group for fully/partially            overlapped PDSCHs        -   . . .

The PDSCHs transmitted from different TRPs will have different TCIstates associated with them. Therefore, according to the aboveagreement, the PDSCH DM-RSs from the different TRPs need to belong todifferent DM-RS CDM groups according to this restriction.

In the case when the PDSCHs are scheduled via DCI format 1-1, theAntenna ports field in the DCI indicates the PDSCH DMRS ports. Hence, inthe case of DCI format 1-1, it can be easily ensured by properindication of the PDSCH DMRS ports that the two PDSCH DM-RSs from thetwo TRPs belong to different DM-RS CDM groups.

However, the case when the PDSCHs are scheduled via DCI format 1-0 isproblematic for multi-PDCCH based NC-JT as there is no Antenna portsfield in DCI format 1-0. In the case of DCI format 1-0, the PDSCH DM-RSis assumed to use DM-RS port 0 which corresponds to CDM group 0. Hence,in the scenario when one or both TRPs are scheduling PDSCH using DCIformat 1-0, then there is a strong possibility that both TRPs' PDSCHDMRS end up in CDM group 0. For Multi-PDCCH based NC-JT, this violatesthe restriction of having different TRPs' PDSCH DM-RS in different DM-RSCDM groups. Hence, a solution should be studied on how to ensure theabove agreed restriction is satisfied when multi-PDCCH based NC-JTscheduling involves DCI format 1-0.

-   Observation 2 For Multi-PDCCH based NC-JT, scheduling PDSCH using    DCI format 1_0 from one or both TRPs violates the restriction of    having different TRPs' PDSCH DM-RS in different DM-RS CDM groups.

Hence, some solution to handle this issue should be discussed in RAN1.

6.6 Clarification on Number of TCI States Per DCI

For multi-DCI scheduling over two TRPs, the original motivation was thateach TRP schedules its PDSCH independently. In that case, each DCI actsin the same way as in Rel-15. Therefore, only one TCI state is instatedin each DCI. Also, multi-DCI operation is distinguished from single DCIwhen there are two higher layer indices configured for the CORESETs. So,we have the following proposal

-   Proposal 24 Multi-DCI is enabled when two higher layer indices for    the CORESETs are configured.-   Proposal 25 When multi-DCI is enabled, only a single TCI state is    indicated in each DCI.-   Proposal 26 When multi-DCI is enabled and two PDSCHs are scheduled    by two DCIs in a slot, the two PDSCHs are indicated with two    different HARQ process IDs.

6.7 PDSCH Type Combinations Supported

(which combinations should be supported: type A+type A, type B+type B,type A+type B)

6.8 Default TCI State CONCLUSION

In the previous sections we made the following observations:

Observation 1 Whether to introduce explicit PUCCH resource groups or notis currently being discussed parallelly in both the Multi-TRP and theMulti-Beam agendas, and if such discussions continue, may result inconflicting agreements.

Observation 2 For Multi-PDCCH based NC-JT, scheduling PDSCH using DCIformat 1_0 from one or both TRPs violates the restriction of havingdifferent TRPs' PDSCH DM-RS in different DM-RS CDM groups.

Based on the discussion in the previous sections we propose thefollowing:

Proposal 1 For single PDCCH case, if two overlapping LTE CRS patternsare configured, the UE shall rate match PDSCH around both LTE CRS, forall received layers.

Proposal 2 When 2 TCI states are indicated in DCI and the K1 value inthe same DCI is below the threshold, the default TCI states are the TCIstates indicated in the DCI or TCIs associated to 2 CORESETs.

Proposal 3 If a TCI codepoint indicates two TCI states and indicatedDMRS ports are from single CDM group, and if repetition scheme is notenabled (i.e. URLLC based scheme not enabled), then the UE applies thefirst TCI state and ignores the second TCI state in the codepoint.

Proposal 4 If a TCI codepoint indicates two TCI states and indicatedDMRS ports are from three CDM groups, then the UE associates the firstTCI state to the first CDM group (λ=0) and the second TCI states to thesecond and third CDM group (λ=1, 2).

Proposal 5 If a UE is scheduled with two codewords and two PTRS ports isconfigured for single-PDCCH based multi-TRP/Panel transmission at leastfor eMBB and URLLC scheme 1a, and if two TCI states are indicated by oneTCI code point, and for each TCI state

if the TCI state is associated to two MCSs (i.e. the TCI state isassociated with two code words) then the first PTRS port is associatedwith the lowest indexed DMRS port assigned for the codeword with thehigher MCS within the DMRS ports corresponding to the TCI state, and

if the MCS indices of the two codewords are the same, then thefirst/second PTRS port is associated with the lowest indexed DMRS portwithin the DMRS ports corresponding to the first/second indicated TCIstate

Proposal 6 If a TCI codepoint indicates two TCI states and indicatedDMRS ports are from single CDM group, and if two PT-RS ports areenabled, then a single PT-RS port is transmitted.

Proposal 7 In Scheme 2a and 2b, a single PT-RS port is used. If twoPT-RS ports have been configured (in case dynamic switching betweenschemes is supported), then only the PT-RS port associated with thelowest index DM-RS port is transmitted.

Proposal 8 In scheme 2a, the UE shall not assume that it can use thePT-RS transmissions from PDSCH resources associated with different TCIstates in a joint manner, when using PT-RS for tracking the phase.Hence, phase tracking needs to be estimated for each of the two groupsof PDSCH resources separately.

Proposal 9 In scheme 2b, the PT-RS resource element mapping isestablished for each of the two PDSCHs independently (i.e. to thescheduled resources of the PDSCH). The UE shall not use PT-RS of onePDSCH as the PT-RS for the other PDSCH.

Proposal 10 In scheme 2b, the value used for the bandwidth NRB whendetermining KPT-RS from Table 5.1.6.3-2 in TS 38.214 is ceil(X/2) whereX is the total number of scheduled resource blocks in the scheme 2bresource allocation.

Proposal 11 For Scheme 2b, use the 4 RV sequences listed in Table 1.

Proposal 12 With regards to restrictions on the possible value pairs forK and SLIV for Scheme 3, the following restrictions apply, and if the UEreceives K and SLIV values in the scheduling DCI that do not satisfy theconditions below, then the UE can assume that only the first repetitionin the slot is transmitted:

-   -   If using the starting symbol of the PDCCH monitoring occasion in        which the DL assignment is detected as the reference point for        starting symbol S is not enabled, then the restriction        0<2L≤14−S−K applies.    -   If using the starting symbol of the PDCCH monitoring occasion in        which the DL assignment is detected as the reference point for        starting symbol S is enabled, then the restriction        0<2L≤14−S−S0−K applies wherein S0 is the starting symbol of the        PDCCH monitoring occasion in which the DL assignment is        detected.

Proposal 13 Support a value range from 0 to 6 for the configurablesymbol offset K.

Proposal 14 In NR Rel-16, the symbol offset K for multi-TRP scheme 3 isconfigured as part of PDSCH-TimeDomainResourceAllocation.

Proposal 15 In NR Rel-16, the maximum number of repetitions for scheme 4is 16.

Proposal 16 In NR Rel-16, the maximum TDRA table size given by‘maxNrofDL-Allocations’ in TS38.331 is 64.

Proposal 17 Up to 4 RV sequences are predefined and the RV field in DCIis re-used to select one of the sequences for Schemes 3 and the same RVsequences as for Scheme 2b are used.

Proposal 18 Either of Scheme 2a, 2b or 3 is semi-statically enabled byRRC. No dynamic switching between these three different schemes issupported. Dynamic fallback to single TRP and/or single repetition issupported.

Proposal 19 Whether or not to introduce explicit PUCCH resource groupsor not should be decided in the Multi-beam agenda.

Proposal 20 In NR Rel-16, explicit association between PUCCH resourcegroups (if agreed in MB agenda) and higher layer signaling indices ofCORESETs is not supported.

Proposal 21 Alt 1 is supported for joint HARQ ACK codebook withmulti-DCI.

Proposal 22 For multi-DCI based multi-TRP/panel transmission, if atleast one LTE CRS patterns is configured, then PDSCH DM-RS is shiftedaccording to Rel.15 procedure when DM-RS symbol collides with LTE CRSsymbol and the shift is always applied for both received PDSCH.

Proposal 23 A UE receiving downlink NC-JT scheduling assignments of twoPDSCHs can ignore both scheduling assignments in case one of thescheduled PDSCH is mapped to REs used for DMRS to the other scheduledPDSCH to the same UE

Proposal 24 Multi-DCI is enabled when two higher layer indices for theCORESETs are configured.

Proposal 25 When multi-DCI is enabled, only a single TCI state isindicated in each DCI.

Proposal 26 When multi-DCI is enabled and two PDSCHs are scheduled bytwo DCIs in a slot, the two PDSCHs are indicated with two different HARQprocess IDs.

REFERENCES

-   [1] R1-1901702 “Further discussion on multi TRP transmission” vivo-   [2] R1-1903043, “Multi-TRP Enhancements” Qualcomm Incorporated-   [3] R1-1905166, “NC-JT performance with layer restriction between    TRPs”, Ericsson, 3GPP RAN1 #96bis.-   [4] R1-1907423, “On MAC-CE signaling impact of Rel-16 TCI indication    framework”, Ericsson, 3GPP RAN1 #97-   [5] R1-1907422, “Performance evaluation of NC-JT with different    clustering approaches”, Ericsson, RAN1 #97-   [6] R1-1905165, “Performance comparison of different RV combinations    for SDM and FDM based schemes”, Ericsson, RAN1 #96bis-   [7] R1-1907425, “Additional evaluation results on multi-TRP schemes    for reliable PDSCH transmission in URLLC”, Ericsson, RAN1 #97.-   [8] R1-1907421, “On the number of TRPs for high reliability at 4    GHz”, Ericsson, RAN1 #97.-   [9] R1-1907420, “Additional evaluation results on NC-JT performance    with layer restriction between TRPs”, Ericsson, RAN1 #97.-   [10] R1-1907515, “On schemes 3 and 4 for URLLC with Multi-TRP”,    Ericsson, RAN1 #97.-   [11] R1-1907426, “On Multi-TRP based URLLC Schemes for Downlink    SPS”, Ericsson, RAN1 #97.-   [12] RP-191599, “Enhancements for dynamic spectrum sharing in    Rel-16”, Ericsson, RAN #84-   [13] R1-1909465, “On multi-TRP and multi-panel”, Ericsson, RAN1 #98.-   [14] R1-1909423, “Preliminary results on PDCCH over multi-TRP for    URLLC”, Ericsson, RAN1 #98.-   [13] R2-1910143, “Protocol structure for Multi-TRP operation”,    Ericsson, RAN2 #107-   [14] R1-1908066, “Enhancements on Multi-TRP/panel transmission”,    Huawei, HiSilicon

The invention claimed is:
 1. A method for a UE in a multipletransmission points communication system, mTRP, the method comprising:receiving a higher layer configuration of a mTRP scheme; receivingdownlink control information, DCI, indicating a first TransmissionConfiguration Indicator, TCI, state and a second TCI state in one CodeDivision Multiplexing, CDM, group for a scheduled data transmission onphysical resource blocks, PRBs, wherein the PRBs comprise at least afirst subset of PRBs, associated with the first TCI state, and a secondsubset of PRBs, associated with the second TCI state; and determining afirst Phase Tracking Reference Signal, PT-RS, frequency density for aPT-RS port in the first subset of PRBs based on a number of PRBs in thefirst subset of PRBs and a second PT-RS frequency density for the samePT-RS port in the second subset of PRBs based on a number of PRBs in thesecond subset of PRBs.
 2. The method according to claim 1, wherein thefirst TCI state is associated with a first transmission point in themultiple transmission points communication system and wherein the secondTCI state is associated with a second transmission point in the multipletransmission points communication system.
 3. The method according toclaim 1, wherein the PT-RS to resource element mapping is associated toallocated PRBs for each TCI state.
 4. The method according to claim 1,wherein the scheduled data transmission comprises one or more physicaldownlink shared channel, PDSCH, transmissions scheduled by the DCI. 5.The method according to claim 1, wherein the first PT-RS frequencydensity and the second PT-RS frequency density are determined for thesame PT-RS port.
 6. The method according to claim 5, wherein the mTRPscheme is one of a frequency division multiplexing, FDM, Scheme 2a,wherein a single PDSCH transmission for a transport block, TB, isscheduled across the first subset of PRBs and the second subset of PRBs,or a FDM Scheme 2b, wherein a first PDSCH transmission for a TB isscheduled in the first subset of PRBs and a second PDSCH transmissionfor the same TB is scheduled in the second subset of PRBs.
 7. The methodaccording to claim 1 wherein the at least the first subset of PRBs andthe second subset of PRBs are non-overlapping.
 8. A user equipment, UE,operable in a multiple transmission points communication system, mTRP,the UE comprising a transceiver and processing circuitry configured to:receive a higher layer configuration of a mTRP scheme; receive downlinkcontrol information, DCI, indicating a first Transmission ConfigurationIndicator, TCI, state and a second TCI state in one Code DivisionMultiplexing, CDM, group for a scheduled data transmission on physicalresource blocks, PRBs, wherein the PRBs comprise at least a first subsetof PRBs, associated with the first TCI state, and a second subset ofPRBs, associated with the second TCI state; and determine a first PhaseTracking Reference Signal, PT-RS, frequency density for a PT-RS port inthe first subset of PRBs based on a number of PRBs in the first subsetof PRBs and a second PT-RS frequency density for the same PT-RS port inthe second subset of PRBs based on a number of PRBs in the second subsetof PRBs.
 9. The UE according to claim 8, wherein the first TCI state isassociated with a first transmission point in the multiple transmissionpoints communication system and wherein the second TCI state isassociated with a second transmission point the multiple transmissionpoints communication system.
 10. The UE according to claim 8, whereinthe PT-RS to resource element mapping is associated to allocated PRBsfor each TCI state.
 11. The UE according to claim 8, wherein thescheduled data transmission comprises one or more physical downlinkshared channel, PDSCH, transmissions scheduled by the DCI.
 12. The UEaccording to claim 8, wherein the first PT-RS frequency density and thesecond PT-RS frequency density are determined for the same PT-RS port.13. The UE according to claim 12, wherein the mTRP scheme is one of afrequency division multiplexing, FDM, Scheme 2a, wherein a single PDSCHtransmission for a transport block, TB, is scheduled across the firstsubset of PRBs and the second subset of PRBs, or a FDM Scheme 2b,wherein a first PDSCH transmission for a TB is scheduled in the firstsubset of PRBs and a second PDSCH transmission for the same TB isscheduled in the second subset of PRBs.
 14. The UE according to claim 8,wherein the at least the first subset of PRBs and the second subset ofPRBs are non-overlapping.
 15. A method for a base station in a multipletransmission points communication system, mTRP, scheme, the methodcomprising: transmitting a higher layer configuration of a mTRP scheme;transmitting downlink control information, DCI, indicating a firstTransmission Configuration Indicator, TCI, state and a second TCI statein one Code Division Multiplexing, CDM, group for a scheduled datatransmission on physical resource blocks, PRBs, wherein the PRBscomprise at least a first subset of PRBs, associated with the first TCIstate, and a second subset of PRBs, associated with the second TCIstate; and wherein a first Phase Tracking Reference Signal, PT-RS,frequency density for a PT-RS port for the first subset of PRBs isobtainable based on a number of PRBs in the first subset of PRBs and asecond PT-RS frequency density for the same PT-RS port in the secondsubset of PRBs is obtainable based on a number of PRBs in the secondsubset of PRBs.
 16. The method according to claim 15, wherein the firstTCI state is associated with a first transmission point in the multipletransmission points communication system and wherein the second TCIstate is associated with a second transmission point in the multipletransmission points communication system.
 17. The method according toclaim 15, wherein the PT-RS to resource element mapping is associated toallocated PRBs for each TCI state.
 18. The method according to claim 15,wherein the scheduled data transmission comprises one or more physicaldownlink shared channel, PDSCH, transmissions scheduled by the DCI. 19.The method according to claim 15, wherein the first PT-RS frequencydensity and the second PT-RS frequency density are determined for thesame PT-RS port.
 20. The method according to claim 19, wherein the mTRPscheme is one of a frequency division multiplexing, FDM, Scheme 2a,wherein a single PDSCH transmission for a transport block, TB, isscheduled across the first subset of PRBS and the second subset of PRBs,or a FDM Scheme 2b, wherein a first PDSCH transmission for a TB isscheduled in the first subset of PRBs and a second PDSCH transmissionfor the same TB is scheduled in the second subset of PRBs.
 21. Themethod according to claim 15 wherein the at least the first subset ofPRBs and the second subset of PRBs are non-overlapping.
 22. A basestation operable in a multiple transmission points communication system,mTRP, scheme, the base station comprising a transceiver and processingcircuitry and configured to: transmit a higher layer configuration of amTRP scheme; transmit downlink control information, DCI, indicating afirst Transmission Configuration Indicator, TCI, state and a second TCIstate in one Code Division Multiplexing, CDM, group for a scheduled datatransmission on physical resource blocks, PRBs, wherein the PRBscomprise at least a first subset of PRBs, associated with the first TCIstate, and a second subset of PRBs, associated with the second TCIstate; and wherein a first Phase Tracking Reference Signal, PT-RS,frequency density for a PT-RS port in the first subset of PRBs isobtainable based on a number of PRBs in the first subset of PRBs and asecond PT-RS frequency density for the same PT-RS port in the secondsubset of PRBs is obtainable based on a number of PRBs in the secondsubset of PRBs.
 23. The base station according to claim 22, wherein thefirst TCI state is associated with a first transmission point in themultiple transmission points communication system and wherein the secondTCI state is associated with a second transmission point in the multipletransmission points communication system.
 24. The base station accordingto claim 22, wherein the PT-RS to resource element mapping is associatedto allocated PRBs for each TCI state.
 25. The base station according toclaim 22, wherein the scheduled data transmission comprises one or morephysical downlink shared channel, PDSCH, transmissions scheduled by theDCI.
 26. The base station according to claim 22, wherein the first PT-RSfrequency density and the second PT-RS frequency density are determinedfor the same PT-RS port.
 27. The base station according to claim 26,wherein the mTRP scheme is one of a FDM Scheme 2a, wherein a singlePDSCH transmission for a transport block, TB, is scheduled across thefirst subset of PRBS and the second subset of PRBs, or a FDM Scheme 2b,wherein a first PDSCH transmission for a TB is scheduled in the firstsubset of PRBs and a second PDSCH transmission for the same TB isscheduled in the second subset of PRBs.
 28. The base station accordingto claim 22 wherein the at least the first subset of PRBs and the secondsubset of PRBs are non-overlapping.